Ever find yourself switching between tabs just to format JSON or decode a JWT? Here are 5 micro-tools that run entirely in your browser — no install, no signup, no tracking.
1. 🔐 Password Strength Analyzer
Paste a password, get instant entropy analysis + crack time estimate. Everything runs client-side.
👉 Try it
2. 📋 JSON Formatter & Validator
Paste messy JSON, get it pretty-printed with syntax highlighting. Catches errors instantly.
👉 Try it
3. 🔑 JWT Decoder
Decode any JWT token — see header, payload, and expiry at a glance. No data leaves your browser.
👉 Try it
4. 📝 Markdown Preview
Write markdown on the left, see rendered HTML on the right. Export-ready.
👉 Try it
5. 🆔 UUID Generator
Generate v4 UUIDs in bulk. Copy with one click. Dead simple.
👉 Try it
All tools are open source, hosted on GitHub Pages, and completely free. No ads, no analytics, no BS.
What micro-tools do you wish existed? Drop a comment — I might build it next 🛠️
Built with vanilla JS because not everything needs React.
🏦 DonFlow — Budget Drift Detector — Plan vs reality budget tracking, 100% in your browser. No backend, no tracking.
📘 Free Resource
If you are building with a $0 budget, I wrote a playbook about what works, what doesn't, and how to think about the $0 phase.
📥 The $0 Developer Playbook — Free (PWYW)
Want the deep dive? The Extended Edition ($7) includes a 30-day launch calendar, 5 copy templates, platform comparison matrix, and revenue math calculator.
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