Dev Toolbox

Fast, privacy-first developer tools. No backend. No tracking. Everything runs locally in your browser.

A collection of essential developer utilities built with SvelteKit. All tools process data entirely in your browser — your data never leaves your device.

Live: https://devtools.dataflowkit.dev

🧰 Tools

• 🔐 JWT Inspector — Decode and inspect JSON Web Tokens with header, payload, and expiration status
• ⏰ Cron Explainer — Understand cron expressions in plain English and preview upcoming runs
• 🕐 Timestamp Converter — Convert between Unix timestamps, ISO 8601, and milliseconds
• 🌐 API Request Builder — Build HTTP requests and generate code snippets (curl, fetch, axios, httpie)
• 📋 JSON Formatter — Prettify, minify, validate, and search JSON with interactive tree view
• 🔤 Base64 Converter — Encode/decode Base64, Base64URL, and Hex with UTF-8 support
• 🔗 URL Inspector — Parse URLs, edit query parameters, and rebuild clean URLs

✨ Key Principles

• Privacy-First
• No Backend
• No Tracking

🛠️ Tech

Built with SvelteKit, TypeScript, and Tailwind CSS.

🧪 Development

npm install
npm run dev

🔒 Privacy

All processing happens locally in your browser.

• No data is sent to any server
• No cookies, tracking, or analytics
• Works offline after initial load

📝 License

MIT

👤 Author

Built and maintained by Anton Bulavenko

☕ Support

If you find this work useful, you can support independent open source software here:
Support

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