A collection of fast, privacy-friendly developer tools that run 100% in your browser.
Live site: usedevutils.com
- No login. Ever. No accounts, no cookies, no tracking walls
- Private by default — every tool runs entirely client-side. Your data never leaves your device (verify it yourself in the network tab)
- Sub-second results — pure static HTML/CSS/JS, no frameworks, no build step, millisecond loads
- No lock-in — open source under MIT. Host it yourself if you want
| Tool | What it does |
|---|---|
| JSON Formatter & Validator | Beautify, minify and validate JSON with precise error locations |
| Base64 Encoder / Decoder | UTF-8 safe encode/decode — Chinese, emoji, all Unicode |
| URL Encoder / Decoder | Percent-encoding in component or full-URI mode |
| Unix Timestamp Converter | Epoch ↔ human dates, auto-detects seconds/milliseconds, live clock |
| Regex Tester | Live match highlighting, capture groups, flag toggles |
| JWT Decoder | Decode headers/payloads, human-readable expiry status |
| UUID Generator | Cryptographically random UUID v4, bulk mode |
| SHA-256 Hash Generator | Live hashing via Web Crypto API |
Plus reference pages: Regex Cheat Sheet, What Is a Unix Timestamp?, and focused single-purpose tools (JSON Validator, JSON Beautifier, Base64 Encode, Epoch Converter, and more).
Deliberately boring, deliberately fast:
- Pure static multi-page HTML — every tool gets its own URL (good for SEO, good for bookmarking)
- Zero npm dependencies, zero build step, zero JavaScript frameworks
- One shared stylesheet (
css/style.css), one file per tool - Long-tail pages generated by
generate_longtail.py
It's a static site — any static host works:
git clone https://github.com/frozenwindcn/devutils.git
cd devutils
python -m http.server 8000
# open http://localhost:8000Or deploy the folder to EdgeOne Pages / Netlify / Vercel / GitHub Pages as-is.
Found a bug or want a new tool? Issues and PRs are welcome.
MIT © 2026 DevUtils