I Built 143 Free Browser Tools That Never Ask You to Sign Up (Here's What I Learned)

I Built 143 Free Browser Tools That Never Ask You to Sign Up (Here's What I Learned)

I kept running into the same frustration: every "free" online tool wanted an account, an email confirmation, and sometimes a credit card before letting me convert a single PDF. So I built the alternative — Toolfyra (https://toolfyra.vercel.app) — a collection of 143 tools that run entirely in your browser, with no sign-up, no uploads, and no watermarks.

This post is the honest technical breakdown: what I built, how the client-side processing actually works, and what I learned shipping it.

The core rule: files never leave the device

Every tool that touches a file processes it with browser APIs only:

• PDF merge/split/compress → pdf-lib (vendored locally, ~1 load, then offline)
• Image compression/conversion/watermarking → HTML5 Canvas + canvas.toBlob()
• Video screenshots & frame sheets → <video> + canvas.drawImage() at any timestamp
• A real slideshow video creator → canvas.captureStream(30) + MediaRecorder → an actual downloadable WebM file, rendered in real time, with optional AudioContext music mixing
• QR codes → generated locally with a vendored qrcode-generator build

No uploads means no server cost, no privacy policy headaches, and no way to lose someone's data — because we never have it.

What's inside (143 tools and counting)

• Money & Tier-1 finance: paycheck estimators (US/UK/CA/AU tax logic), 401(k) growth, FIRE number, UK stamp duty, mortgage affordability, auto lease-vs-buy, net worth with benchmarks
• AI-era helpers: prompt generators for Midjourney/Sora-style models, multi-scene consistent prompt sets, video-to-prompt, token counter with editable per-million rates
• PDF & images: merge, split, compress, convert, watermark — all client-side
• Developer tools: JSON formatter, JWT decoder, cron builder, regex tester, Base64, UUID
• Health: body fat (US Navy method), macros, TDEE, heart-rate zones (Karvonen), blood-pressure categories
• Test data: fake name/address/person generators (clearly fictional, RFC-reserved email domains), plus honest validators (Luhn card checker, E.164 phone formatter)
• Debt Payoff Coach: snowball/avalanche simulation, debt-free-date projection, milestone tracking — all in localStorage

A few favorites: Universal Downloader (paste a YouTube/TikTok link, grab thumbnails + screenshots), Slideshow Video Maker (photos → real video file), ATS Resume Scanner (job-description keyword match, computed locally).

Things I learned building it

1. package.json with "type": "module" silently changes your test workflow. My Node test suite (jsdom-based deep-interaction tests for every page) needed a .cjs rename. Small thing, cost me an hour.

2. Mobile isn't a checkbox. Every tool got rebuilt around touch targets, viewport meta, and RTL support — the interface auto-translates into 13 languages based on navigator.language (with proper dir="rtl" for Arabic/Urdu), while content stays English for SEO.

3. The AI-era web needs machine-readable doors. I added an llms.txt, a full llms-full.txt reference with every tool's FAQ answers, and a tools.json catalog — plus explicit allow-lists for AI crawlers in robots.txt. If AI assistants are the new front page, they should be able to read your site.

4. Honest UX beats dark patterns. The "video downloader" doesn't pretend to rip DRM'd streams — it does everything genuinely possible in a browser (thumbnails, metadata, screenshots) and says so. Trust compounds.

5. Testing 143 pages is a job for jsdom, not humans. The test suite loads every page, clicks the buttons, and asserts the math (tax brackets, Luhn checks, snowball schedules). Currently 145/145 passing on every deploy.

Try it, break it, tell me

The whole thing is free, no account, nothing tracked: toolfyra.vercel.app

If you find a bug or want a tool that doesn't exist yet, drop a comment — shipping new tools weekly.