Every developer has been there — you need to quickly format some JSON, decode a JWT, or check a regex pattern. You Google it, land on a site plastered with ads, wonder if your data is being logged, and reluctantly paste your API response anyway.
I decided to fix this for myself by building Nyx Dev Tools — a collection of 14 free developer utilities that run entirely client-side.
The Tools
| Tool | What It Does |
|---|---|
| JSON Formatter | Format, validate, and minify JSON |
| Base64 Encoder/Decoder | Encode and decode Base64 strings |
| UUID Generator | Generate random v4 UUIDs |
| Hash Generator | MD5, SHA1, SHA256 hash generation |
| Regex Tester | Real-time regex matching with highlighting |
| JWT Decoder | Decode and inspect JWT tokens |
| Timestamp Converter | Unix timestamp ↔ human dates |
| URL Encoder/Decoder | Percent-encode/decode URLs |
| Color Converter | Convert between HEX, RGB, HSL |
| Markdown Preview | Live markdown editor with preview |
| Password Generator | Cryptographically random passwords |
| Lorem Ipsum Generator | Configurable placeholder text |
| CSS Minifier | Minify and beautify CSS |
| HTML Formatter | Format and minify HTML |
Why Client-Side Matters
Every tool runs in your browser using JavaScript. Your data never leaves your machine. No server processing, no logging, no "we may use your input to improve our service."
This matters when you're pasting:
- API responses with auth tokens
- JWT tokens from production
- Database query results
- Configuration files with secrets
The Stack
Deliberately minimal:
- HTML/CSS/JS — no React, Vue, or any framework
- Cloudflare Pages — free hosting, global CDN
- No build step — edit a file, deploy
- No dependencies — zero npm packages
Each tool is a single HTML file with embedded JavaScript. No bundler, no transpiler, no node_modules.
Developer Guides
I also wrote 15 reference guides that pair with the tools:
- Git Commands Cheat Sheet
- Regex Guide
- Docker Commands
- SQL Cheat Sheet
- CSS Grid & Flexbox
- HTTP Status Codes
- JWT Security
- And more on Base64, UUIDs, timestamps, markdown, HTML colors, and environment variables
What's Next
Planning to add:
- Cron expression builder — visual cron schedule creator
- Diff checker — compare two text blocks
- QR code generator — generate QR codes client-side
- Image to Base64 — convert images without uploading
Try It Out
All tools are free, no signup required. If there's a tool you'd want added, let me know in the comments.
Top comments (0)