DEV Community: Chris

Best HTML to PDF API Tools for Developers in 2026

Chris — Sun, 14 Jun 2026 07:18:45 +0000

Key takeaways

HTML2PDF.app is built as a browser based HTML to PDF API that focuses on real SaaS workloads, like invoices, receipts, reports, and exporting app views, with strong CSS and JavaScript support. The guide explains how to evaluate HTML to PDF APIs on rendering quality, developer experience, performance, reliability, security, and pricing, then shows where HTML2PDF.app fits compared to other providers and when to choose self hosted options.

Key points:

Prefer a browser based HTML to PDF API that behaves like modern Chromium so your PDFs match what users see in the app, including Flexbox, Grid, and JavaScript heavy pages.
Focus on developer experience, a single simple POST endpoint, clear docs, examples, and good logs, so you can get from zero to first PDF in minutes and debug issues quickly.
Match the API’s pricing and hosting model to your workload, small SaaS, high volume batch, side project, or strict compliance, to avoid surprise bills and security gaps.
Structure your HTML and CSS for print, use page break classes, stable headers and footers, and correct asset hosting to get predictable, high quality PDFs from any provider.
Always test 2 to 4 HTML to PDF APIs with your real templates and measure output quality, latency, errors, and cost before you commit.

Topic	Key Insight	Why It Matters	Action Item
Role of HTML to PDF APIs	An HTML to PDF API lets you convert HTML or URLs to PDFs via HTTP instead of running your own headless browser stack.	Offloading PDF rendering saves time, avoids maintaining Chrome clusters, and improves reliability for documents like invoices and reports.	Replace home grown PDF scripts with a managed HTML to PDF API when your app depends on regular PDF generation.
Rendering quality	Browser based engines with full CSS and JavaScript support produce PDFs that closely match modern web app layouts.	Complex UIs built with React, Vue, Tailwind, Grid, and Flexbox need real browser behavior to avoid broken layouts and bad page breaks.	Choose APIs that emulate modern Chromium, then test them with your most complex templates and SPA pages.
Developer experience	A simple REST endpoint, clear parameters, and language examples cut integration time and reduce bugs.	Fast integration and easy debugging are vital when PDFs are part of core flows, such as billing or reporting.	Pick a service where you can do a single POST with `html` or `url` and get a PDF, and verify quickstarts for your main language.
Performance and scale	APIs must handle bursts, concurrency, and long running jobs without timeouts, especially for SaaS billing and batch exports.	Slow or fragile PDF generation can block user actions, delay invoices, or overload your backend.	Load test 50 to 100 conversions of heavy templates, check async and webhook support, and confirm serverless friendliness.
Security and data handling	PDF APIs process sensitive content like invoices and contracts, so HTTPS, auth, and clear data retention matter.	Weak security or unclear retention can put PII or legal documents at risk.	Review each provider’s security docs, retention policy, and regional options, and avoid sending extra personal data.
Pricing alignment	Pricing models differ by conversion, page, or tier, which can affect costs as your volume grows.	A model that seems cheap at low volume can become expensive at scale or during spikes.	Estimate monthly documents and pages, then simulate costs for each provider’s plan before choosing.
When HTML2PDF.app fits best	HTML2PDF.app targets SaaS style workloads with browser like rendering, simple REST API, and developer friendly pricing.	It reduces the need to run headless Chrome while handling real world CSS and JavaScript at scale.	Use HTML2PDF.app for invoices, receipts, reports, and “Download as PDF” features where you want quick setup and reliable output.
When to use other providers	Some tools specialize in advanced print layout, mixed file conversions, or self hosted deployment.	Different use cases, like legal grade pagination or strict on premise rules, may need specialized engines or self hosting.	For very complex print documents evaluate advanced layout providers, and for strict compliance consider self hosted engines such as Gotenberg.
Template and CSS design	PDFs improve when HTML is structured for print, with clear widths, print media styles, and explicit page breaks.	Browser centric layouts alone often lead to awkward breaks, clipped content, or inconsistent headers in PDFs.	Add `@media print` rules, page break classes, fixed header/footer heights, and absolute URLs for assets in your templates.
Evaluation process	The most reliable way to choose an API is to test several providers with your real templates and measure quality, speed, and errors.	Marketing claims do not reveal how an API behaves with your HTML, CSS, and load patterns.	Define 3 to 4 representative documents, integrate 2 to 4 APIs behind a small abstraction, benchmark output and cost, then pick the best fit.

Best HTML to PDF API tools for developers in 2026

The best HTML to PDF API for your project in 2026 is the one that matches your real workload, not just a feature list. For most SaaS apps that generate invoices, receipts, reports, and exports directly from HTML, a browser-based HTML to PDF API with strong CSS and JavaScript support, a simple REST interface, good speed, and predictable pricing will outperform everything else.

That is exactly the use case we built HTML2PDF.app for.

In this guide we, the team behind HTML2PDF.app, share how we think about picking the best HTML to PDF API, how we designed our own HTML to PDF conversion API, and how it compares to other options like PDFCrowd, ConvertAPI, PDFEndpoint, PDFShift, DocRaptor, API2PDF, and Gotenberg.

This article is written for developers and technical decision makers who care about:

High quality HTML to PDF rendering with real CSS and JavaScript
Clean REST APIs and good examples
Latency, throughput, and scalability
Reliability, status visibility, and support
HTML to PDF API pricing that matches real usage patterns

We will keep the language practical and focused on real-world use, so you can decide faster.

What an HTML to PDF API is and why developers rely on it

The core idea: an HTML to PDF API lets you convert HTML to PDF via API calls instead of running your own browser or PDF toolchain.

You send HTML or a URL to an HTML to PDF REST API, it spins up a rendering engine similar to a headless browser, loads your HTML, applies CSS and JavaScript, then returns a PDF file.

In 2026, developers use an HTML to PDF API for:

Invoices, receipts, and billing statements
Order confirmations and tickets
Reports and dashboards
Contracts and agreements
Exporting app views as PDFs for offline or legal use

Modern front ends are more complex now. React, Vue, Angular, Tailwind, CSS Grid, and Flexbox are standard. Many teams want pixel perfect output that looks exactly like the app view.

Running and patching your own headless Chrome cluster just for PDF generation is painful. That is why HTML to PDF conversion API services are popular. You get:

A stable browser-based HTML to PDF service
Simple HTTP calls instead of managing rendering infrastructure
Built in handling for concurrency, queues, and scale

When we built HTML2PDF.app, we had the same pain: we needed a fast, predictable way to generate PDFs from real, CSS heavy pages without babysitting headless Chrome. That experience still shapes how we design our HTML to PDF API today.

How we evaluated the best HTML to PDF APIs

The best HTML to PDF API in 2026 is not one single product. It depends on your documents, volume, and constraints. To keep this guide honest, here is the framework we use when we compare HTML to PDF conversion API options, including our own.

Rendering engine and quality

Answer first: Prefer a browser based HTML to PDF API that behaves like a modern Chromium browser, with strong CSS and JavaScript support.

Key questions:

Does it emulate a modern browser, or a legacy engine?
Does it support Flexbox, Grid, media queries, web fonts, SVG, and responsive images?
Does it handle tricky page breaks, headers, footers, and page numbers?
Does it support SPA frameworks like React, Vue, and Angular, including client-side rendering and hydration?

In practice, you want high quality HTML to PDF rendering that matches what Chrome prints when you hit “Print” in the browser.

Developer experience

Answer first: A good HTML to PDF API should let you convert HTML to PDF via API with a single POST, minimal options, and clear examples.

We look for:

A simple HTML to PDF REST API endpoint, clear required and optional params
SDKs or samples for Node.js, Python, PHP, Ruby, Java, .NET, Go
Clean, copy paste ready docs and quickstarts
Test consoles, playgrounds, logs, and dashboards that make debugging easy

We judge this by how fast we can get from zero to first PDF in a real codebase.

Performance and scalability

Answer first: Your HTML to PDF API should stay fast and stable under load, even when you generate thousands of PDFs.

Key points:

Typical latency for a single conversion, for example small invoice vs long report
Concurrency limits, rate limits, and burst handling
Support for asynchronous PDF generation for long running jobs
Bulk HTML to PDF conversion patterns, like queue based or batch APIs
Whether it can work in a serverless PDF generation setup without timeouts

Reliability and security

Answer first: Treat PDF generation like any other production dependency, you need uptime, security, and clear data handling.

We look at:

Uptime history and public status pages
HTTPS everywhere
Data retention policy, how long HTML and PDFs stay on servers
Encryption in transit, and if relevant in storage
Regions or data residency options, EU vs US
On-premise or self hosted options when needed

For a secure HTML to PDF API, we want the safest default behavior possible, because many PDFs contain invoices, PII, or contracts.

Pricing and value

Answer first: Match the HTML to PDF API pricing model to your usage pattern so you do not get surprised later.

Common models:

Per conversion or per document
Per page
Subscription tiers with soft limits
Enterprise contracts

We map this against:

Low volume and side projects
Growing SaaS with bursty usage
High volume batch jobs

We also pay attention to free tiers or trials, so you can test before committing.

Extra capabilities

Answer first: Advanced features matter when your workflow is more than “HTML in, PDF out”.

Useful extras:

Support to generate PDFs from URL, raw HTML, or stored templates
Headers, footers, page numbers, and watermarks
Password protection, merging, or splitting PDFs
Webhooks and asynchronous PDF generation
Serverless friendly behavior

We used this same checklist when we shaped HTML2PDF.app, so we will refer back to it below.

HTML2PDF.app overview a fast and developer friendly HTML to PDF API

The best fit for most SaaS and web apps that need reliable, fast HTML to PDF with modern CSS support is a focused, developer first HTML to PDF API. That is exactly what we built with HTML2PDF.app.

What HTML2PDF.app is

Answer first: HTML2PDF.app is a developer focused HTML to PDF API that converts HTML and URLs into PDFs quickly, with browser like rendering, via a simple REST API.

We designed HTML2PDF.app for:

Programmatic PDF generation from HTML strings
Converting live app pages by URL to PDF
Rendering HTML templates stored in your systems

Typical use cases we see:

Billing systems generating invoices and receipts
Analytics dashboards exporting reports
Customer portals offering “Download as PDF”
Internal tools that need PDF snapshots of HTML views

Our own internal products needed all of these. We got tired of babysitting headless Chrome processes, so we built a stable HTML to PDF conversion API and then productized it as HTML2PDF.app.

Core technical features

Answer first: HTML2PDF.app provides a REST based HTML to PDF API with a modern rendering engine similar to headless Chromium.

Core behavior:

Clean HTML to PDF REST API endpoint
Support for generating PDFs from URL or raw HTML
Browser based HTML to PDF rendering that supports:

- Flexbox and CSS Grid layouts

- Print and screen media queries

- Web fonts, SVG, retina images

- JavaScript execution for SPAs and dynamic content

Key features you can typically control via API:

Page size: A4, Letter, or custom dimensions
Orientation: portrait or landscape
Margins and DPI for sharper output
Headers and footers, including dynamic content like page numbers or timestamps
Options to delay rendering to wait for JavaScript to finish

In practice, you can send the same HTML you show in your app and get a high quality HTML to PDF rendering that is suitable for production.

Developer experience with HTML2PDF.app

Answer first: We built HTML2PDF.app so you can convert HTML to PDF via API in a single POST call from any language.

From a developer view:

Simple REST API, no heavy SDK requirement
Clear quickstart examples in common languages such as Node.js, Python, PHP, Ruby, Java, .NET
Minimal configuration, sane defaults for page size, margins, and engines
API key based authentication
Sandbox or test mode so you can try things without affecting live quotas

A typical flow to generate PDFs from URL might look like:

1. Get an API key from the HTML2PDF.app dashboard

2. Send a POST request with url or html plus optional settings

3. Receive a PDF file as the response or a link to download

You do not need to run any local binaries or install special drivers.

Performance and scalability

Answer first: HTML2PDF.app is built to handle both on demand and batch HTML to PDF generation at speed.

We focus on:

Fast conversion times for single documents like invoices
Stable behavior under bursts, such as end-of-month billing
Parallel processing support to generate many PDFs at once

Typical patterns we see:

A SaaS app generating a PDF for each order placed
A background job that does bulk HTML to PDF conversion for thousands of reports
Serverless PDF generation from platforms like AWS Lambda or Vercel functions

We design our HTML to PDF service to be a scalable HTML to PDF service, so you do not have to run or scale your own headless Chrome fleet.

Security and reliability

Answer first: HTML2PDF.app uses secure defaults and short lived data handling suitable for sensitive PDFs like invoices and reports.

In practice:

All requests go over HTTPS
You authenticate using API keys
We treat HTML and generated PDFs as transient data, typically stored only as long as needed to process and deliver the file
We monitor uptime and performance internally and operate as a managed SaaS HTML to PDF service

If you work in a sensitive domain, you should always read any secure HTML to PDF API’s data retention and privacy docs. We encourage that for HTML2PDF.app as well, and we keep our policies straightforward.

Pricing and best fit

Answer first: HTML2PDF.app uses developer friendly HTML to PDF API pricing that works for both small projects and growing apps.

Typical traits:

Free trial or low entry tier so you can test with real templates
Predictable plans based on conversions or usage
Options for higher volume workloads

Where HTML2PDF.app fits best:

SaaS products that need reliable PDF invoices and receipts
Internal reporting tools that generate PDFs from HTML dashboards
Any app that wants to convert HTML to PDF via API at scale without running browsers

You choose HTML2PDF.app when:

You want a simple, fast, and reliable HTML to PDF API
You want browser like rendering, including JavaScript, without hosting headless Chrome
You want an HTML to PDF REST API that feels natural to use from modern codebases

Leading HTML to PDF API providers compared in 2026

The HTML to PDF API space in 2026 has several solid options, each with a slightly different focus. Here is a neutral overview using the same criteria.

PDFCrowd

Answer first: PDFCrowd is an HTML to PDF API focused on converting HTML and URLs into PDFs with strong, production ready rendering.

Based on their docs, PDFCrowd:

Supports converting HTML, URLs, and templates to PDF via API
Emphasizes browser like rendering for web pages and application content
Targets production workloads for invoices, reports, and web snapshots

Developer experience:

Provides REST endpoints and client libraries in multiple languages
Offers a straightforward workflow, you POST HTML or URLs and receive a PDF
Documentation focuses on practical examples for web apps and backend services

This makes PDFCrowd a good fit if you already have a lot of URL based content and want consistent HTML to PDF conversion from live pages. You can see more on their site at pdfcrowd.com.

ConvertAPI

Answer first: ConvertAPI is a general file conversion platform with a specific HTML to PDF conversion API endpoint.

Capabilities:

Offers many conversions, including HTML to PDF, DOCX to PDF, images, and more
Lets you control formatting and output options per conversion
Supports converting both URLs and raw HTML to PDF

Developer experience:

Simple POST based workflow to convert HTML to PDF via API
Multiple language libraries and examples
Clear docs focusing on speed and accuracy for conversions in general

ConvertAPI is suitable if you need HTML to PDF plus other conversion types such as DOCX or images in the same stack. Their HTML to PDF page explains the workflow at convertapi.com.

PDFEndpoint

Answer first: PDFEndpoint is a lightweight HTML to PDF API that targets simplicity and cost sensitive use cases.

Capabilities:

HTML to PDF conversion with focus on quality output
Control over page size, margins, and formatting
Built for quick integrations and small to medium workloads

Developer experience:

Simple REST based API
Positioning toward being free or low cost for many cases
Clear examples for quick setup

PDFEndpoint is often attractive for side projects or smaller apps where a free or very low budget HTML to PDF API matters. Their site at pdfendpoint.com highlights the lightweight approach.

PDFShift

Answer first: PDFShift is an HTML to PDF API that focuses on modern HTML and CSS support.

Capabilities:

Likely based on a modern browser engine
Designed to handle advanced CSS like Flexbox and Grid
Targets developers who need high fidelity output from complex layouts

Ideal if you have a heavy CSS front end and you care strongly about print perfect rendering.

DocRaptor

Answer first: DocRaptor is an HTML to PDF API aimed at advanced print layout and enterprise grade documents.

Capabilities:

Very fine control over page layout
Strong support for headers, footers, and complex pagination
Good for legal, compliance, and print quality documents

You might look at DocRaptor if you have extremely detailed print requirements or long form documents like policies, contracts, or books.

API2PDF

Answer first: API2PDF is a PDF generation API that acts as an aggregator of engines for HTML to PDF and other PDF tasks.

Capabilities:

Supports HTML to PDF through multiple engines such as wkhtmltopdf or headless Chrome
May offer other PDF operations like merging and stamping

Engine flexibility allows you to choose trade offs between speed and fidelity without changing providers.

Gotenberg

Answer first: Gotenberg is mainly a self hosted, Docker based HTML to PDF conversion service.

Capabilities:

Runs in your own infrastructure or Kubernetes cluster
Uses Chromium or other engines to convert HTML to PDF
Good for in house deployments where data cannot leave your environment

Gotenberg fits teams with strict data residency or compliance rules that require self hosted PDF generation rather than a SaaS HTML to PDF API.

A comparison from OneSimpleAPI lists PDFShift, DocRaptor, API2PDF, Gotenberg, and others as common choices alongside PDFCrowd, ConvertAPI, and PDFEndpoint, which matches what we see in the market.

Comparison table of HTML to PDF APIs

Answer first: Use this table as a quick HTML to PDF API comparison, then test 2 to 4 services with your own templates.

Provider	Rendering approach	Complex CSS & JS	API simplicity	Pricing orientation	Hosting model	Best suited for
HTML2PDF.app	Browser based, Chromium like	Yes	Simple	Free / paid developer plans	SaaS	SaaS apps and services needing fast, reliable HTML to PDF API
PDFCrowd	Browser like	Yes	Simple	Subscription / usage based	SaaS	Production HTML and URL based PDFs
ConvertAPI	Browser like, multi format	Yes	Moderate	Pay as you go / plans	SaaS	Apps needing many file conversions plus HTML to PDF
PDFEndpoint	Browser based	Partial to Yes	Simple	Free oriented / low cost	SaaS	Side projects, low budget deployments
PDFShift	Modern browser engine	Yes	Simple	Usage based	SaaS	Apps with advanced CSS layouts
DocRaptor	Print grade engine	Yes, advanced	Advanced	Higher tier / enterprise	SaaS	Complex, print ready and compliance documents
API2PDF	Multiple engines (Chrome, wkhtmltopdf)	Yes	Moderate	Usage based	SaaS	Teams wanting engine choice and extra PDF ops
Gotenberg	Self hosted browser engine	Yes	Moderate	Infra cost only, OSS image	Self hosted	Strict compliance and on premise needs

We recommend shortlisting 2 to 4 services including HTML2PDF.app, then running the tests described later to choose the best HTML to PDF API for your setup.

Choosing the right HTML to PDF API for your use case

The best HTML to PDF API for you depends mostly on your documents and volume. Use these scenarios as a guide.

For common SaaS invoices and reports

Answer first: For most SaaS apps that generate invoices, receipts, and simple reports from HTML, use a browser based HTML to PDF conversion API with simple REST calls and strong reliability.

Priorities:

High quality HTML to PDF rendering for typical app layouts
Reasonable, predictable HTML to PDF API pricing
Easy integration and good docs
Enough performance to handle peak events like billing cycles

In this scenario:

Primary recommendation: HTML2PDF.app, because it focuses on HTML to PDF API use cases like invoices and reports, is easy to integrate, and avoids overhead of managing your own browser stack.
Alternatives: PDFCrowd or ConvertAPI if you already use their ecosystem, or if you also want other conversions beyond HTML to PDF.

For complex print ready documents

Answer first: For long, complex, and print grade documents like contracts or policies, pick an HTML to PDF API that is known for advanced print layout.

Priorities:

Precise control over pagination, headers, footers, and page numbers
Multi column support and advanced CSS for print
Stable output that looks the same over time

Recommendations:

Start with HTML2PDF.app if your templates are HTML and CSS oriented but not extremely exotic. Our browser based HTML to PDF service handles most modern layouts out of the box.
If your needs are very specialized, for example legal documents with strict layout rules, evaluate an HTML to PDF API like DocRaptor that markets advanced print layout capabilities.

Always test with your actual templates before deciding. Print layout is where small CSS details can matter a lot.

For high volume and back end workloads

Answer first: For large batch jobs or continuous high volume HTML to PDF generation, you need an HTML to PDF API that handles concurrency, queues, and async patterns.

Priorities:

Strong concurrency and rate limit policies
Support for asynchronous PDF generation and webhooks if jobs are long running
Clear SLAs or at least a strong uptime record
Ability to queue or schedule bulk HTML to PDF conversion jobs

In this scenario:

HTML2PDF.app works well as a scalable HTML to PDF service for bursty SaaS workloads and scheduled jobs, and we designed it with parallel processing in mind.
For extremely high volume or mixed conversion types, also check platforms like ConvertAPI or API2PDF.

Build a small load test that runs 50 to 100 conversions of your heaviest templates to see how latency behaves.

For side projects and low budgets

Answer first: For a side project, prototype, or hobby app, pick an HTML to PDF API with a free tier and minimal setup.

Priorities:

Free tier or very low starting cost
Very simple setup and integration
Enough reliability for non mission critical use

In this case:

HTML2PDF.app is a good fit if you want a simple, developer friendly HTML to PDF REST API and can start on a low cost or trial plan.
PDFEndpoint is another example of a lightweight HTML to PDF API that targets cost sensitive use cases.

You can always switch providers later if your project grows, so focus on getting an HTML to PDF conversion API that lets you move quickly.

For strict compliance and on premise needs

Answer first: When documents cannot leave your infrastructure, you need self hosted HTML to PDF generation rather than a pure SaaS HTML to PDF API.

Priorities:

Ability to run the HTML to PDF engine in your own cloud or data center
Compliance with internal security policies
Clear and auditable data flow

Here, Gotenberg is a strong option, as it runs as a container in your own environment. Some teams also wrap headless Chrome themselves, but that adds maintenance overhead.

You can still use HTML2PDF.app in hybrid setups where only non sensitive HTML is sent to the SaaS HTML to PDF API, and sensitive content uses an internal renderer.

Implementation tips for reliable HTML to PDF conversion

Answer first: Structure your HTML and CSS for print, not just for the browser, and your HTML to PDF API results will improve immediately.

From working with many client templates at HTML2PDF.app, here are practical tips.

Structure HTML for predictable PDFs

Use semantic HTML where possible
Avoid complex nested tables for layout if you can use Flexbox or Grid
Use print specific styles:

css @media print { .no-print { display: none; } .page-break { page-break-before: always; } }

Keep content widths consistent, for example a max width on your main container

Handling page breaks, headers, and footers

Most HTML to PDF APIs including HTML2PDF.app support CSS page break hints, for example:

css.page-break { page-break-before: always;}

Design your templates so natural break points (section ends, chapter starts) line up with these classes.

For headers and footers:

Use API options for repeating headers and footers if available
Keep header/footer height fixed to avoid layout surprises
Add page numbers through the API or with generated content if supported

Managing fonts, assets, and images

HTML to PDF conversion API services run in their own environment, not your browser session, so:

Host assets over HTTPS with public access or secure but reachable URLs
Use absolute URLs for images and CSS
Prefer web safe fonts or host your font files and reference them via @font-face
Use suitable resolution images, not overlarge, to keep PDFs fast to render and download

Dealing with JavaScript heavy pages

If you have an SPA:

Either send pre rendered HTML to the HTML to PDF API
Or use an HTML to PDF conversion API that supports JavaScript execution and lets you set a render delay

In HTML2PDF.app, we support executing JavaScript and waiting before capturing the PDF output. This is important if your React or Vue app loads data asynchronously.

Performance and reliability patterns

To keep your HTML to PDF API usage fast and stable:

Cache pre rendered HTML for documents that change rarely
Use a job queue for bulk HTML to PDF conversion so you do not overload your own app
Implement retries with backoff for transient errors
Add logging for HTML to PDF failures including status codes and payload size

These patterns help with any HTML to PDF API, not just HTML2PDF.app.

Security and reliability considerations for PDF generation APIs

Answer first: Treat any HTML to PDF API as part of your security surface, especially when handling invoices, PII, or contracts.

Security checklist for any secure HTML to PDF API:

TLS/HTTPS for all endpoints
Authentication, usually via API keys or tokens
Data retention policy that states how long HTML and PDFs live on servers
Logging practices that avoid storing sensitive content in logs
Regional options if you need EU or US specific processing
Uptime and status visibility, such as a status page or published uptime metrics

When you use HTML2PDF.app, we encourage you to:

Use HTTPS and keep your API keys safe
Avoid sending unnecessary personal data in HTML if you do not need it in the PDF
Read our data handling and retention docs so you know exactly what happens to your HTML and PDFs

For highly sensitive cases, you may combine HTML2PDF.app with internal redaction or anonymization. For ultra strict compliance, you may choose a self hosted engine like Gotenberg alongside or instead of an external HTML to PDF API.

A practical checklist to test HTML to PDF APIs

Answer first: The best way to pick the best HTML to PDF API is to test 2 to 4 providers with your real templates and measure.

Use this step by step approach:

1. Define test cases

- A simple invoice

- A complex report with graphs and tables

- A long, multi page document

- An SPA page that relies on JavaScript

2. Select 2 to 4 APIs

- Include HTML2PDF.app

- Add one or more of PDFCrowd, ConvertAPI, PDFEndpoint, DocRaptor, API2PDF, PDFShift, or Gotenberg depending on your needs

3. Implement basic integrations

- In your main language (Node, Python, etc.)

- Keep a common wrapper so you can switch the HTML to PDF API easily

4. Measure behavior

- Output fidelity, layout, fonts, images, page breaks

- Response time for each conversion type

- Stability over 50 to 100 conversions per template

- Error clarity when something fails

5. Compare pricing vs volume

- Estimate monthly number of PDFs and pages

- Apply each HTML to PDF API pricing model to your estimate

- Include hidden costs like potential overages

6. Assess developer experience

- How clear are the docs

- How easy are examples to adapt

- How responsive is support

7. Make a choice and keep flexibility

- Pick the HTML to PDF API that balances quality, performance, and cost for your workload

- Wrap it in an abstraction so you can swap later if needed

We follow a similar process when we evaluate APIs we use internally, and we designed HTML2PDF.app to perform well across these steps.

FAQ about HTML to PDF APIs

Q&A 1

Question: What is an HTML to PDF API?

Answer: An HTML to PDF API is a web service that converts web pages or raw HTML code into PDF documents programmatically. Developers send HTML (and often CSS and JavaScript) to the API endpoint, and the service returns a rendered PDF file that preserves layout, styling, and content. This is commonly used for invoices, reports, receipts, contracts, and other documents generated from web applications.

Q&A 2

Question: How does an HTML to PDF API work?

Answer: An HTML to PDF API typically accepts a URL or raw HTML input via an HTTP request. The service uses a rendering engine (similar to a headless browser) to load the HTML, apply CSS and JavaScript, and then generate a PDF based on the rendered page. The API then responds with the PDF file or a download link. Many APIs also provide options for page size, margins, headers and footers, and other PDF settings.

Q&A 3

Question: What should I look for in the best HTML to PDF API?

Answer: Important factors include: quality and accuracy of rendering (CSS/JS support, fonts, images), performance and reliability, scalability, pricing, ease of integration (SDKs, documentation, examples), security (HTTPS, authentication, data handling), and customization options (page size, margins, headers/footers, templates). Good support and clear rate limits are also important when choosing an API.

Q&A 4

Question: Is it secure to use an HTML to PDF API for sensitive documents?

Answer: Security depends on how the API is implemented. A secure HTML to PDF API should use HTTPS for all requests, support authentication (such as API keys or tokens), and have clear policies about data retention and storage. Some services process documents in memory and do not store content after conversion. For highly sensitive data, you may also want features like on premise or private cloud deployment options.

Q&A 5

Question: Can I automate generating PDFs from my website using an HTML to PDF API?

Answer: Yes. You can integrate an HTML to PDF API into your backend or serverless functions to automatically generate PDFs whenever certain events occur, such as a user placing an order, submitting a form, or requesting a report. By sending the relevant URL or HTML to the API and storing or emailing the returned PDF, you can fully automate document generation from your website or web application.

Final thoughts choosing the best HTML to PDF API for 2026

Answer first: There is no single HTML to PDF API that is perfect for every project, but you can make a clear choice once you match your needs to the right type of service.

To recap:

For most SaaS apps that generate invoices, receipts, and reports from HTML, a browser based HTML to PDF API like HTML2PDF.app is usually the best balance of simplicity, speed, and reliability.
If you need advanced print layout for complex documents, an HTML to PDF API like DocRaptor could be a better fit.
If you want mixed conversions, platforms like ConvertAPI can help.
For strict compliance, self hosted options like Gotenberg matter.

Our focus with HTML2PDF.app is to give developers a fast, simple, and reliable HTML to PDF REST API that:

Handles real world CSS and JavaScript
Scales with your workloads
Stays easy to integrate and maintain over time

Your next step:

1. Take one of your real HTML templates, an invoice or report.

2. Sign up for HTML2PDF.app and get an API key.

3. Call the HTML to PDF API once from your app or a script and inspect the PDF.

You should be able to convert HTML to PDF via API in just a few minutes.

From there, use the checklist above to compare HTML2PDF.app with any other HTML to PDF API you are considering, and pick the service that fits your workload best.

How to generate and send PDF invoices automatically using n8n and HTML2PDF.app

Chris — Sun, 07 Jun 2026 07:31:49 +0000

I’ve published a new tutorial on how to generate and send PDF invoices automatically using n8n and HTML2PDF.app.

The guide shows how to collect invoice data from a form, generate an HTML invoice template, convert it to PDF, and send it by email as an attachment.

Read the full tutorial here:
https://html2pdf.app/blog/generate-and-send-pdf-invoice-with-n8n/

Generate invoice PDF file using HTML template

Chris — Tue, 05 Sep 2023 13:24:26 +0000

Today, I'll walk you through the process of generating an invoice PDF file for your backend app or custom script which could be run from the command line. Let's get started! 🎉

Introduction

Node.js programming language will be used for simplicity.
Handlebars template engine to separate data from the presentation.
html2pdf.app to convert HTML to PDF, but as an alternative Puppeteer can be used also (you can find a complete tutorial How to convert HTML to PDF with puppeteer).

Project structure

Let's assume we are creating a new project "generate-invoice", first Create a directory using the command mkdir generate-invoice. Then initialize a Node.js project by entering the command npm init and provide all the necessary information.

Now we need to install dependencies, which will be used. For that run the command npm i handlebars axios.

Having all the needed dependencies, let's create a conversion file using the command mkdir src && touch src/generate.js.

Now we need to store the template where the HTML code will be provided. Create a templates directory and invoice.html file for that with the command mkdir templates && touch templates/invoice.html.

This simple project structure is enough to start writing the code. Your project should look like this tree below.

├── package-lock.json
├── package.json
├── node_modules
├── src
│   └── generate.js
└── templates
    └── invoice.html

Prepare the template

Before diving into the conversion process, you'll need to create an HTML template for your invoice. This template will define the layout, content, and styling of your PDF invoice.

There are many invoice HTML templates you can find on Google. I am going to use an already created one, whose code source you can find here

In the end, it should look the following:

Feel free to customize the HTML template to match your branding and invoicing needs. You can update fonts, and colours, add your company logo, and include any necessary details like invoice number, customer information, etc.

Put your template HTML code into the templates/invoice.html file and let's move to the next step.

Convert HTML to PDF

First, we need to add needed dependencies to the conversion script.

import fs from 'fs';
import Handlebars from 'handlebars';
import axios from 'axios';

Now we can load the invoice HTML code into the Handlebars template.

const invoice = fs.readFileSync('./assets/invoice.html', 'utf8');
const template = Handlebars.compile(invoice);

Also, we need to set parameters which will be binded into the template, they can come from various places in your real project. For example database, Excel file, command line arguments and so on. I will define those parameters in the script directly for simplicity.

const params = {
    invoiceNr: 'H2P202307-01711',
    billTo: 'Anna Smith',
    invoiceDate: (new Date()).toDateString(),
    paymentDue: (new Date()).toDateString(),
    orderId: 112233,
    items: [
        {description: 'Domain registration', quantity: 2, price: '$10', total: '$20'},
        {description: 'Web hosting', quantity: 1, price: '$15', total: '$15'},
        {description: 'Consulting', quantity: 1, price: '$500', total: '$500'},
    ],
    subTotal: '$535',
    tax: '$53.5',
    total: '$588.5',
};

Now we can process the template by passing the parameters and get the result - the final HTML code which will be converted to the PDF document.

const html = template(params);

There are multiple options for how to convert HTML to PDF, one could be by using open-source projects like Puppeteer or wkhtmltopdf. I wrote a separate post How to convert HTML to PDF using Puppeteer, but now for simplicity, I going to use html2pdf.app. Its free plan gives 100 credits per month, excellent!

To register and get the free API key use the link: https://dash.html2pdf.app/registration

Once you have an API Key, let's finish the conversion part.

const apiKey = '******************'; // API key from https://html2pdf.app

const response = await axios.post('https://api.html2pdf.app/v1/generate', {
    html,
    apiKey,
}, {responseType: 'arraybuffer'});

To send the HTML code to the PDF conversion API there are only a few lines of code. Now what needs to be done is to save the response. For that add the code line below to your script.

fs.writeFileSync('./assets/invoice.pdf', response.data);

The complete conversion script code looks as follows:

import fs from 'fs';
import Handlebars from 'handlebars';
import axios from 'axios';

const invoice = fs.readFileSync('./assets/invoice.html', 'utf8');
const template = Handlebars.compile(invoice);
const params = {
    invoiceNr: 'H2P202307-01711',
    billTo: 'Anna Smith',
    invoiceDate: (new Date()).toDateString(),
    paymentDue: (new Date()).toDateString(),
    orderId: 112233,
    items: [
        {description: 'Domain registration', quantity: 2, price: '$10', total: '$20'},
        {description: 'Web hosting', quantity: 1, price: '$15', total: '$15'},
        {description: 'Consulting', quantity: 1, price: '$500', total: '$500'},
    ],
    subTotal: '$535',
    tax: '$53.5',
    total: '$588.5',
};

const html = template(params);
const apiKey = 'd3a0264f70864...'; // get api key on https://html2pdf.app

const response = await axios.post('https://api.html2pdf.app/v1/generate', {
    html,
    apiKey,
}, {responseType: 'arraybuffer'});

fs.writeFileSync('./assets/invoice.pdf', response.data);

You can find it on GitHub also https://github.com/html2pdfapp/examples/blob/main/src/generate-invoice.js

Conclusion

I like not to mix business logic or data with the presentation layer, and currently, there is a much clearer solution when we have a template separated from the data.

The simplicity of html2pdf.app API and its free plan allow us to save time and only with a few lines of code, we have the converted PDF file you can store it somewhere in the cloud or project directory.

Happy coding!

How to convert HTML to PDF using Puppeteer

Chris — Fri, 21 Jul 2023 19:29:07 +0000

Whether you're looking to generate invoices, create reports, or preserve web content for offline use, Puppeteer is a powerful tool that can automate the process seamlessly. In this guide, we will explore how to convert HTML to PDF using Puppeteer, an open-source Node.js library developed by Google.

Setting Up Puppeteer

To get started, you'll need to have Node.js installed on your machine. Open your terminal or command prompt and create a new directory for your project. Navigate into the project directory and initialize a new Node.js project by running the following command:

npm init -y

Next, install Puppeteer as a dependency by executing the following command:

npm install puppeteer

Puppeteer will now be added to your project, allowing you to programmatically control a headless Chrome or Chromium browser.

Writing the conversion script

Create a new JavaScript file, such as convert-html-to-pdf.js, in your project directory. Open the file in your preferred text editor and begin by importing the Puppeteer library:

const puppeteer = require('puppeteer');

Initializing Puppeteer and Converting HTML to PDF

Inside the convert-html-to-pdf.js file, add the following code to initialize Puppeteer and convert the HTML to PDF:

(async () => {
  try {
    const browser = await puppeteer.launch();
    const page = await browser.newPage();
    await page.goto('file:///path/to/your/html/file.html', { waitUntil: 'networkidle0' });

    // To use normal CSS instead of only print styles
    await page.emulateMediaType('screen');

    await page.pdf({ path: 'output.pdf', format: 'A4' });

      console.log('Conversion complete. PDF file generated successfully.');

      await browser.close();
    } catch (error) {
      console.error('An error occurred:', error);
    }

})();

The example shows how to convert an existing html file to the pdf, but you might be needed to convert html code which could be passed as a parameter to the puppeteer. In this case function page.setContent() should be used. Check the example below:

const html = '<html...';
await page.setContent(html, { waitUntil: 'networkidle0' });

Converting URL to PDF

You can easily update the code to convert an URL instead of HTML or file, by passing the URL to the page.goto method:

await page.goto('https://example.com', { waitUntil: 'networkidle0' });

It is important to understand waitUntil parameter and it's values to choose a proper one.

load: when load event is fired.
domcontentloaded: when the DOMContentLoaded event is fired.
networkidle0: when there are no more than 0 network connections for at least 500 ms.
networkidle2: when there are no more than 2 network connections for at least 500 ms.

For more detailed information, which options can be passed to the puppeteer.goto method check the puppeteer documentation.

Break down the code

We have created an async function using an immediately invoked function expression (IIFE) to ensure proper execution. Inside the function, we launched a new instance of the Puppeteer controlled browser.

We open a new page and navigate to the desired HTML file using the page.goto() method. Make sure to replace 'file:///path/to/your/html/file.html' with the actual path to your HTML file. By specifying { waitUntil: 'networkidle0' }, we ensure that the page is fully loaded before generating the PDF.

It is necessary to execute method: page.emulateMediaType('screen'); to have fully loaded CSS.

Finally, we call page.pdf() to convert the HTML to PDF and specify the output path and format. Adjust the path and format properties as needed. After successful conversion, we log a message and close the browser instance.

Running the conversion script

Save the convert-html-to-pdf.js file, navigate to your project directory in the terminal or command prompt, and run the following command:

node convert-html-to-pdf.js

Puppeteer will launch a headless browser, load the HTML file, convert it to PDF, and save the output as output.pdf in the project directory.

Using html2pdf.app API

Managing Puppeteer can be chalanging task, especially if you need to scale up the application. Huge number of the requests can break the server performance since PDF conversion requires quite many resources.

Make your life easier by using html to pdf API to convert PDFs.

Following code shows how it is simple todo with our api:

import axios from 'axios';
import fs from 'fs';

axios.post('https://api.html2pdf.app/v1/generate', {
  html: 'https://example.com',
  apiKey: '{your-api-key}',
}, {responseType: 'arraybuffer'}).then((response) => {
  fs.writeFileSync('./document.pdf', response.data);
}).catch((err) => {
  console.log(err.message);
});

Conclusion

By following the steps outlined in this guide, you can easily convert HTML files to PDF using Puppeteer. This versatile library opens up a world of possibilities for automating document generation, report creation, and more.

If you do not want to struggle with some edge cases and have a fast result, try already built in solutions to convert PDFs like html2pdf.app.

Happy coding!

My journey of making a side project which makes passive incomes

Chris — Sun, 15 May 2022 18:41:09 +0000

Hello, I want to share my story of how I have created my side project of html2pdf.app. You can see from the domain that it is the HTML to PDF conversion API.

Working as a full-time developer I was living quite a normal and good life. But one thought from time to time was coming to my head - creating my own project which makes money.

I decided to do something for a very specific niche, to avoid high competitiveness and where I have some experience. So I came up with the idea that a HTML to PDF API conversion service online would be a great one to start with.

Almost in every company where I worked, I had to implement some PDF generation feature and in old times it was very challenging to do.

How did I start

When I was starting a new project I decided to learn something new at the same time. Also if my project would not be successful at least I could learn something useful.

Being a PHP developer for a long time I had also experience with JavaScript and at that time the NodeJS framework was quite interesting to me. Also, I knew that there is a Headless Chrome engine which is very convenient to use with the Puppeteer library.

I noticed that using Headless Chrome converted PDFs are high quality and quite similar compared to the HTML. I understood that Headless Chrome has the power and I need to leverage it!

Since I have a full-time job and family, it was a challenge for me to find time to develop my side project. So I started to work on weekends, very slowly but I was moving forward.

NodeJS framework was unfamiliar to me and took significantly more time to do the same things which I could do with PHP. I did not know even how to use the debugger, or how to structure my app from the beginning. But after some time I was feeling more comfortable in this stack.

Tech stack

These are technologies that I have chosen to use. One thing which I would change is perhaps choosing golang instead of NodeJS.

NodeJS/TypeScript + ExpressJS/NestJS frameworks;
Mysql for permanent data storage;
MongoDB for storing conversions logs;
Redis for caching;
RabbitMQ for async jobs and async communication between microservices;

Also, I integrated third-party services like sentry, mailgun, stripe, mailerlite which are very helpful and make developer's life easier.

Microservices architecture

Since I chose microservices architecture things became even more complicated. It took a bit of time to set up multiple services to make communication among them proper.

So from my practice, I would suggest once you are doing a startup/side project and are focusing on how to make money not gain experience in a new field, skip new/fancy technologies, and create a monolith system, which could be scaled further.

The diagram below illustrates the relations between the microservices of my project.

Where to get customers?

So finally I launched my service totally free. My plan was to get new customers and make sure that my service is useful to somebody. And actually, it was useful, new clients were registering, and I do not know how I became on the first page of a Google Search by keyword “HTML to pdf API”. I also set up Google AdWords to get more new customers.

First paid customer

After some time I noticed that customers who are using the HTML to PDF conversion service are very grateful, some of them even asked how to send money for using the service. So I decided to monetize the service and establish a small company to make everything legal.

I left a free plan for the clients with limited conversions per month and also created paid plans, and things started moving forwards. I was very happy when I could cover server expenses and pay taxes without using my own money.

Currently, I have over 50 paying clients, not many but still a good achievement for me making passive incomes.

Challenges I faced

First of all, NodeJS has no static typing so it was very uncomfortable for me, even an IDE didn’t show autocompletion.

I was struggling with this for some time and decided to use TypeScript, so rewrote all the code in this language. It took some time to rewrite and set up the project to use TypeScript but it was definitely worth it.

Headless Chrome scalability and AWS Lambda

Another challenge I encountered was scalability because I was using a headless chrome engine just directly installed into the server where applications run.

From time to time I noticed that one instance of Headless Chrome sometimes crashed when there are more requests. So after some attempts to solve this problem, I decided to try the AWS Lambda function and the results were stunning.

It scales automatically and is able to handle high loads. Setting up a working Lambda function and Puppeteer library was a bit challenging but I managed it successfully.

Conclusion

As I wanted to learn and develop a project at the same time, I decided to use microservices architecture to gather more experience and this was a mistake.

I spent a lot of time making microservices work and increased the complexity of the whole infrastructure. If I could give a suggestion for someone who is starting a startup I wouldn’t recommend chasing cutting-edge technologies and definitely do not start with microservices.

Create an MVP first, and check how your audience is reacting to your product and what changes you need to make after the feedback. Then when you see that your project could be beneficial do some cleanups, refactoring, splitting things into microservices, etc.

No doubts, I learned a lot of new things and got an experience that I could not get at work working on regular projects.

There are many things that could be improved and make service better, but overall, I am happy to have created this project and had this experience.

I feel like I am growing as a professional by learning new things, and solving problems at the same time making my side project better.

That was my story, hope you enjoyed reading it. If somebody is interested more to know technical details I could answer with pleasure in the comments.