I kept opening random websites for small tasks — formatting JSON, decoding JWTs, converting timestamps, generating UUIDs. Different sites, different UX, most wanting sign-ups or tracking everything.
So I built devprix.dev — 56 developer tools that all run in your browser. Nothing sent to any server. Zero npm dependencies for any tool logic.
The Full Tool List
Formatters & Validators
- JSON Formatter (beautify, minify, tree view)
- SQL Formatter (6 SQL dialects)
- Regex Tester (live highlighting, pattern library)
- JWT Decoder (header/payload/signature, expiry check)
- Cron Expression Parser (visual builder, next run times)
- JSON Path Evaluator & JSON Validator
Generators
- UUID Generator (v1, v3, v4, v5, v7)
- Password & Key Generator (RSA, ECDSA, Ed25519 key pairs)
- QR Code Generator (URL, WiFi, vCard — encoder built from scratch)
- Test Data Generator (55+ field types)
- Hash Generator (MD5, SHA-1/256/384/512, HMAC)
Converters
- Timestamp / Epoch Converter (80+ timezones)
- Base64 Encoder/Decoder
- Color Converter (HEX/RGB/HSL, WCAG contrast checker, palettes)
- YAML ↔ JSON (Docker/K8s presets)
- JSON → TypeScript (interfaces, Zod schemas)
- Curl → Code (Python, JS, Go, Java, PHP, Rust, C#, Ruby)
- CSV ↔ JSON, Markdown ↔ HTML, Image → Base64, and more
DevOps & Config
- Docker Run → Compose (and reverse)
- Chmod Calculator, IP Subnet Calculator
- Git Command Builder (18 commands with danger warnings)
CSS & Design
- CSS Gradient Generator (linear/radial/conic, 24 presets)
- Box Shadow Generator (multi-layer, Tailwind output)
- Tailwind CSS Lookup (500+ classes, reverse lookup)
- Favicon Generator
...plus diff checker, JSON diff, slug generator, ASCII art generator, line tools, and more.
The Interesting Technical Bits
QR Code Encoder From Scratch
Instead of using a library, I implemented the full QR encoding
Myers Diff Algorithm
The text diff checker uses Eugene Myers' 1986 algorithm — the same one behind git diff. It finds the shortest edit script and then does a second pass for character-level highlighting within changed lines, so you can see exactly which characters were modified.
Curl to Code Parser
Parsing curl commands is surprisingly tricky. The parser handles single and double quoted strings, backslash line continuations, --data-raw vs -d vs --data-binary, multiple -H headers, -u for auth, and generates idiomatic code for 9 languages — not just string concatenation but proper library usage (requests for Python, fetch for JS, net/http for Go).
Client-Side Cryptography
The password generator and hash tools use the Web Crypto API (SubtleCrypto) for RSA, ECDSA, and Ed25519 key pair generation, SHA hashing, and HMAC computation. MD5 is the one exception — since Web Crypto doesn't support MD5, that's implemented from scratch.
Zero dependencies is liberating.
No supply chain risk, no breaking updates, no bundle bloat.
Every algorithm is right there in the codebase. The trade-off is development time — implementing a QR encoder takes longer than npm install qrcode — but the result is faster, smaller, and fully under your control.
Dark mode is table stakes.
The site supports light, dark, and system-preference themes. In 2026, shipping a developer tool without dark mode is leaving users behind.
Try It
→ devprix.dev
All free, all private, all in your browser. I'd love to hear what tools you'd want added.
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