DEV Community: Ahmer Arain

How to Convert PNG to WebP (And Why Your Website Needs It)

Ahmer Arain — Sun, 17 May 2026 20:56:40 +0000

If you're still serving PNG images on your website, you're leaving performance on the table.

Google has been pushing WebP for years. It's smaller than PNG, loads faster, and directly impacts your Core Web Vitals score — which affects your SEO ranking. The switch from PNG to WebP is one of the easiest performance wins you can make.

Here's everything you need to know — and how to convert your images for free without uploading them anywhere.

What Is WebP?

WebP is a modern image format developed by Google. It supports both lossless and lossy compression, transparency (like PNG), and animation (like GIF).

The numbers speak for themselves:

WebP lossless images are 26% smaller than PNGs
WebP lossy images are 25-34% smaller than JPEGs at equivalent quality
Supported by all modern browsers — Chrome, Firefox, Safari, Edge

Why PNG to WebP Matters for Performance

Every kilobyte of image data your browser has to download slows your page load. Slower pages mean:

Higher bounce rates
Lower Core Web Vitals scores (LCP, CLS)
Lower Google search rankings
Worse user experience on mobile

Switching from PNG to WebP is one of the fastest wins in web performance. You keep the same visual quality — you just deliver it in a smaller package.

How to Convert PNG to WebP for Free

ConvertifyHub converts PNG to WebP entirely in your browser. No upload, no server, no account needed. Your files never leave your device.

Step 1

Go to convertifyhub.net and open the Image Converter.

Step 2

Drop your PNG file. Batch conversion is supported — drop multiple files at once.

Step 3

Select WebP as the output format. Adjust the quality slider if needed (80-85% is the sweet spot for most web images).

Step 4

Download your WebP file and replace the PNG on your website.

Done. No upload, no account, no cost.

PNG vs WebP — Full Comparison

Feature	PNG	WebP
Lossless compression	✅	✅
Lossy compression	❌	✅
Transparency	✅	✅
Animation	❌	✅
File size	Larger	~26% smaller
Browser support	Universal	All modern browsers
Best for	Print, editing	Web delivery

The Right Quality Setting

WebP quality works on a scale of 0–100. Here's a quick guide:

90-100% — Near lossless. Great for product images, photography where detail matters
80-85% — Sweet spot for most web images. Significant size reduction, no visible quality loss
70-75% — Good for thumbnails, background images, decorative elements
Below 70% — Noticeable quality loss. Avoid for anything important

For most websites, 80-85% gives you the best size-to-quality ratio.

How to Use WebP on Your Website

In HTML

<picture>
  <source srcset="image.webp" type="image/webp">
  <img src="image.png" alt="Description">
</picture>

The <picture> element serves WebP to browsers that support it and falls back to PNG for older browsers.

In CSS

.hero {
  background-image: url('hero.webp');
}

In Next.js

Next.js automatically optimizes and converts images to WebP when you use the <Image> component:

import Image from 'next/image'

<Image src="/hero.png" alt="Hero" width={800} height={600} />

Next.js handles the WebP conversion at build time. You don't even need to manually convert.

In React with Vite

Vite can handle image optimization with plugins like vite-plugin-imagemin:

npm install vite-plugin-imagemin --save-dev

Other Ways to Convert PNG to WebP

Using cwebp (Command Line)

Google's official WebP encoder:

# Install
brew install webp  # macOS
sudo apt install webp  # Ubuntu

# Convert single file
cwebp -q 85 image.png -o image.webp

# Batch convert all PNGs in a folder
for f in *.png; do cwebp -q 85 "$f" -o "${f%.png}.webp"; done

Using Sharp (Node.js)

const sharp = require('sharp');

sharp('input.png')
  .webp({ quality: 85 })
  .toFile('output.webp');

Using Squoosh (Google's Tool)

Google's Squoosh is another browser-based option. Also client-side, great for single image optimization with detailed control.

Using ConvertifyHub (Easiest)

No installation, no command line, no Node.js. Just open convertifyhub.net, drop your PNGs, and download WebPs. Works on any device.

Checklist: Migrating Your Site to WebP

[ ] Audit your current images — find the largest PNGs
[ ] Convert them to WebP using ConvertifyHub or cwebp
[ ] Use <picture> tags with PNG fallback for older browser support
[ ] Update CSS background images to WebP
[ ] Test Core Web Vitals before and after with PageSpeed Insights
[ ] Set up automated WebP conversion in your build pipeline

Wrapping Up

PNG is great for editing and archiving. For web delivery, WebP is almost always the better choice — smaller files, faster loads, better SEO.

Converting is free and takes seconds. If you want to do it without uploading your images to a server, ConvertifyHub handles it entirely in your browser.

No upload. No account. Just convert.

👉 Try ConvertifyHub →

About the Author

Ahmer Arain — Full-stack developer specializing in MERN stack, Next.js, and AWS. Builder of ConvertifyHub and Eternally.

🌐 ahmerarain.com
💼 linkedin.com/in/ahmer-arain
🐙 github.com/ahmerarain

How to Convert HEIC to JPG for Free (Without Uploading Your Photos)

Ahmer Arain — Sat, 02 May 2026 19:18:49 +0000

You just took the perfect photo on your iPhone. You try to share it, upload it, or open it on your Windows PC — and nothing works.

That's HEIC. Apple's default photo format since iOS 11. Great for storage, terrible for compatibility.

The good news? Converting HEIC to JPG takes less than 10 seconds. And you don't need to upload your photos to any server to do it.

What Is HEIC?

HEIC (High Efficiency Image Container) is Apple's modern image format. It compresses photos to roughly half the size of a JPEG while maintaining the same quality. That's why your iPhone uses it by default — it saves storage.

The problem? Almost nothing outside Apple's ecosystem supports it natively:

Windows can't open HEIC without extra software
Most websites reject HEIC uploads
Android doesn't support it
Many older apps can't read it

So at some point, you need to convert.

The Privacy Problem With Most Online Converters

Search "HEIC to JPG converter" and you'll find dozens of tools. Most of them work the same way:

You upload your photo to their server
Their server converts it
You download the result
Your photo sits on their server for some period of time

Your wedding photos. Your kids. Your personal documents. Uploaded to a random server you know nothing about.

There's a better way.

Convert HEIC to JPG Without Uploading — Using ConvertifyHub

ConvertifyHub converts HEIC to JPG entirely in your browser. No upload, no server, no account needed.

Here's how:

Step 1

Go to convertifyhub.net and open the Image Converter.

Step 2

Drop your HEIC file (or click to browse). You can convert multiple files at once.

Step 3

Select JPG as the output format. Adjust quality if needed.

Step 4

Click Convert and download your JPG instantly.

That's it. Your photo never left your device.

Why "In-Browser" Conversion Is Better

ConvertifyHub uses the browser's native Canvas API and WebAssembly to process your files locally. Here's what that means for you:

✅ Privacy — files stay on your device
✅ Speed — no upload/download wait time
✅ Free — no subscription, no limits
✅ No account — just open and convert

Other Ways to Convert HEIC to JPG

On iPhone (Prevent HEIC at the source)

Go to Settings → Camera → Formats and select Most Compatible. Your iPhone will shoot in JPG from now on instead of HEIC.

On Mac

Open the HEIC file in Preview, then go to File → Export and choose JPG.

On Windows

Microsoft offers a free HEIC Image Extensions pack from the Microsoft Store. Install it and Windows Photos can open HEIC files natively. To convert, open in Paint and save as JPG.

Using ConvertifyHub (Any Device)

Works on Windows, Mac, Linux, Android, iPhone — any device with a modern browser. No installation needed.

HEIC vs JPG — Quick Comparison

	HEIC	JPG
File Size	Smaller (~50%)	Larger
Quality	Excellent	Excellent
Compatibility	Apple only	Universal
Web Support	Limited	Full
Best For	iPhone storage	Sharing & uploading

Wrapping Up

HEIC is a great format for your iPhone's storage — but JPG is still king for sharing, uploading, and compatibility. The good news is converting is quick and easy.

If privacy matters to you (and it should — these are your personal photos), use a tool that doesn't upload your files. ConvertifyHub handles the conversion entirely in your browser, for free.

No upload. No account. No nonsense.

👉 Try ConvertifyHub →

About the Author

Ahmer Arain — Full-stack developer specializing in MERN stack, Next.js, and AWS. Builder of ConvertifyHub and Eternally.

🌐 ahmerarain.com
💼 linkedin.com/in/ahmer-arain
🐙 github.com/ahmerarain

How I Built a File Converter That Never Touches Your Files published

Ahmer Arain — Wed, 29 Apr 2026 19:25:35 +0000

I've used plenty of online file converters. Most of them upload your files to some server, process them, then (hopefully) delete them. You're trusting a stranger's backend with your documents, photos, or sensitive data.

I didn't love that. So I built ConvertifyHub — a file converter that supports 150+ formats and processes everything locally, right in your browser. Your files never leave your device.

Here's how I built it and what I learned along the way.

The Core Idea: Client-Side Everything

The whole product is built around one constraint: no file uploads, no server, no database.

That means every conversion — image, document, audio, video, archive — has to happen in the browser using JavaScript and WebAssembly. This is harder to build, but the payoff is massive:

Zero privacy risk for the user
No infrastructure cost for conversions
Instant processing (no round-trip to a server)
Works offline once loaded

The Stack

Frontend:   Next.js (TypeScript)
Deployment: AWS
Processing: Client-side JS + WebAssembly libraries

No backend for file processing. No database. Just a fast frontend deployed on AWS.

How Each Tool Works Under the Hood

Image Conversion

For image conversion I use the browser's native Canvas API combined with libraries like sharp.js compiled to WebAssembly. The user drops a file, it gets read via FileReader, drawn to a canvas, then exported in the target format as a Blob.

const img = new Image();
img.src = URL.createObjectURL(file);
img.onload = () => {
  const canvas = document.createElement('canvas');
  canvas.width = img.width;
  canvas.height = img.height;
  const ctx = canvas.getContext('2d');
  ctx.drawImage(img, 0, 0);
  canvas.toBlob((blob) => {
    // Trigger download
    const url = URL.createObjectURL(blob);
    downloadFile(url, outputName);
  }, targetMimeType, quality);
};

Audio & Video

This was the trickiest part. I used FFmpeg compiled to WebAssembly (@ffmpeg/ffmpeg). It's the same FFmpeg you'd run on a server — but running entirely in the browser via WASM.

import { createFFmpeg, fetchFile } from '@ffmpeg/ffmpeg';

const ffmpeg = createFFmpeg({ log: false });
await ffmpeg.load();

ffmpeg.FS('writeFile', inputName, await fetchFile(file));
await ffmpeg.run('-i', inputName, outputName);
const data = ffmpeg.FS('readFile', outputName);

The file never leaves the browser. FFmpeg runs in a sandboxed WASM environment.

Document Conversion

This one has limitations — true DOCX-to-PDF conversion server-side is always going to be more reliable. But for many use cases (txt, csv, basic formats) the browser handles it well.

The Tools I Ended Up Building

What started as "just an image converter" turned into a full suite:

Image Converter — 25+ formats including WebP, AVIF, HEIC
Image Resizer & Compressor
Audio Converter — MP3, WAV, FLAC, AAC, OGG (via FFmpeg WASM)
Video Trimmer
Document Converter
Archive Converter — ZIP, RAR, 7Z, TAR
Spreadsheet Converter — XLSX, CSV, TSV
Unit & Digital Converters — 50+ units, number bases, color formats
QR & Barcode Generator
Code Minifier & Beautifier
Font Converter — TTF, OTF, WOFF, WOFF2
Security Tools — JWT, hashing, encryption utilities
JSON → TOON Converter — for LLM token optimization
Website Image Scraper
SVG Optimizer
Markdown Converter

That's 20+ tools, all running client-side.

What Made This Hard

1. WebAssembly Loading Time

FFmpeg WASM is ~25MB. First load is slow. I lazy-load it only when the user actually needs audio/video conversion, and show a progress indicator.

2. Memory Limits

Browsers cap memory. Large files (especially video) can crash the tab. I added file size warnings and chunk large files where possible.

3. Format Support Gaps

Not every format has a good JS/WASM library. HEIC on some browsers is still a pain. I had to pick my battles and clearly communicate unsupported edge cases.

4. Cross-Browser Consistency

Canvas API behaves differently across browsers for certain image formats. Lots of testing across Chrome, Firefox, Safari.

The Privacy-First Architecture

No file uploads means:

No S3 buckets storing user files
No database needed
No GDPR headaches around file storage
No server costs per conversion

The only infra I run is serving the Next.js frontend on AWS. That's it.

What's Next

More batch processing support
Better progress indicators for large files
PWA support for offline use
More AI-assisted format recommendations

Try It

👉 convertifyhub.net

No account needed. No upload. Just drop a file and convert.

If you're building something privacy-sensitive and wondering whether you can move processing to the client — in many cases, you can. WebAssembly has made things possible in the browser that used to require a backend. I'd love to hear if you've taken a similar approach.

Drop a comment if you have questions about any part of the stack!

About the Author

Ahmer Arain — Full-stack developer specializing in MERN stack, Next.js, and AWS. I build scalable web and mobile products, from SaaS platforms to marketplace apps.

🌐 ahmerarain.com
💼 linkedin.com/in/ahmer-arain
🐙 github.com/ahmerarain
📧 ahmerarain18@gmail.com

DEV Community: Ahmer Arain

How to Convert PNG to WebP (And Why Your Website Needs It)

What Is WebP?

Why PNG to WebP Matters for Performance

How to Convert PNG to WebP for Free

Step 1

Step 2

Step 3

Step 4

PNG vs WebP — Full Comparison

The Right Quality Setting

How to Use WebP on Your Website

In HTML

In CSS

In Next.js

In React with Vite

Other Ways to Convert PNG to WebP

Using cwebp (Command Line)

Using Sharp (Node.js)

Using Squoosh (Google's Tool)

Using ConvertifyHub (Easiest)

Checklist: Migrating Your Site to WebP

Wrapping Up

About the Author

How to Convert HEIC to JPG for Free (Without Uploading Your Photos)

What Is HEIC?

The Privacy Problem With Most Online Converters

Convert HEIC to JPG Without Uploading — Using ConvertifyHub

Step 1

Step 2

Step 3

Step 4

Why "In-Browser" Conversion Is Better

Other Ways to Convert HEIC to JPG

On iPhone (Prevent HEIC at the source)

On Mac

On Windows

Using ConvertifyHub (Any Device)

HEIC vs JPG — Quick Comparison

Wrapping Up

About the Author

How I Built a File Converter That Never Touches Your Files published

The Core Idea: Client-Side Everything

The Stack

How Each Tool Works Under the Hood

Image Conversion

Audio & Video

Archives

Document Conversion

The Tools I Ended Up Building

What Made This Hard

1. WebAssembly Loading Time

2. Memory Limits

3. Format Support Gaps

4. Cross-Browser Consistency

The Privacy-First Architecture

What's Next

Try It

About the Author