I Built a Free Dev Toolbox That Runs 100% in Your Browser

Rishu — Sat, 21 Mar 2026 10:02:54 +0000

We've all done it.

You're debugging a production issue at 2am. You have a JWT
token you need to decode right now. So you Google
"JWT decoder online", click the first result, and paste
your token into some random website.

That token contains your user's data. Their email.
Maybe their role. Maybe their ID.

And you just handed it to a server you know nothing about.

The Problem

Most online developer tools are built to collect data.
Every time you paste a JWT, JSON payload, or API response
into one of these sites — that data hits their server.
It gets logged. Maybe stored. Maybe sold.

As developers we know better. But we do it anyway because
it's convenient.

What I Built

I built dev-tools.run —
a collection of 13 developer tools that run entirely
in your browser.

No server. No database. No logging. No tracking.
Your data never leaves your device. Ever.

Tools Included

Data & Encoding

✅ JSON Formatter & Validator
✅ Base64 Encoder / Decoder
✅ URL Encoder / Decoder
✅ Markdown Preview

Auth & Tokens

✅ JWT Decoder
✅ UUID / Nano ID Generator
✅ Hash Generator (MD5, SHA-256, SHA-512)

Dev Utilities

✅ Regex Tester
✅ Diff Checker
✅ Cron Parser

Numbers & Colors

✅ Binary / Hex / Decimal Converter
✅ Color Converter (HEX ↔ RGB ↔ HSL)
✅ Unix Timestamp Converter

Tech Stack

Built with:

React + Vite — fast, lightweight
React Router — each tool has its own URL
Web Crypto API — for hashing (no libraries needed)
Zero backend — deployed as a static site on Vercel

The whole thing is a static site. No API calls.
No environment variables. No secrets.

DEV Community: Rishu

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