WhetKit — Free online developer tools. 100% client-side, privacy-first, zero uploads.
A collection of free, privacy-first, client-side developer tools — all running entirely in your browser with zero server uploads.
Live site: https://whetkit.me/
git clone https://github.com/DiyarCeylan/WhetKit.git
cd WhetKit
npx serve .Open http://localhost:3000. Every tool is a single HTML file — no build step, no dependencies.
| # | Tool | Description |
|---|---|---|
| 1 | URL Encoder / Decoder | Encode and decode URL strings |
| 2 | Base64 Encoder / Decoder | Encode text/files to Base64 and decode back |
| 3 | UUID Generator | Generate UUID v1, v4, v7 in bulk |
| 4 | JSON to CSV Converter | Convert JSON arrays to CSV with nested flattening |
| 5 | JSON Formatter & Validator | Format, validate, and minify JSON |
| 6 | Regex Tester | Test regular expressions in real-time |
| 7 | HTML Entity Encoder / Decoder | Encode/decode HTML special characters |
| 8 | JWT Parser | Decode and inspect JWT tokens |
| 9 | Color Converter | Convert between HEX, RGB, HSL, OKLCH |
| 10 | Text Diff Checker | Side-by-side text comparison |
| 11 | HEX to HSL | Convert hex colors to HSL |
| 12 | Base64 Image Converter | Images to/from Base64 data URIs |
| 13 | Epoch Converter | Unix timestamp to human date and back |
| 14 | HTML Preview | Live HTML/CSS/JS sandbox |
| 15 | SQL Formatter | Format and beautify SQL queries |
| 16 | URL Shortener | Shorten long URLs instantly |
- 100% client-side — no data ever leaves your device
- Zero dependencies — every tool is a single HTML file with vanilla JS
- Dark / Light theme — system-aware with manual toggle
- PWA ready — installable, works offline
- No tracking, no cookies — fully private
- SEO optimized — JSON-LD structured data, sitemap, OG tags
- Mobile-first responsive design
| Technology | Usage |
|---|---|
| HTML5 | Semantic structure |
| CSS3 (vanilla) | OKLCH color system, CSS Grid, Flexbox, design tokens |
| JavaScript (vanilla ES6) | All tool logic, theme toggle, localStorage |
| JetBrains Mono / DM Mono | Monospace typefaces (Google Fonts) |
| Google AdSense | Privacy-friendly ad placements |
| Schema.org JSON-LD | Structured data for SEO |
Zero frameworks, zero build tools, zero package dependencies.
/
├── index.html # Tool hub with search
├── favicon.svg # Brand icon
├── manifest.json # PWA manifest
├── robots.txt / sitemap.xml # SEO
├── blog/ # 16 educational guides
├── base64-encoder-decoder/ # Tools (one directory each)
├── color-converter/
├── uuid-generator/
├── json-formatter-validator/
├── ... # All other tools
└── LICENSE
Push to master — GitHub Pages serves the root automatically at whetkit.me.