About DevTools

DevTools is a free, ad-free collection of everyday developer utilities — a JSON formatter, Base64 and URL encoders, a JWT decoder, a Unix timestamp converter, a UUID generator, a hash calculator, and a regex tester. It exists to do one thing well: give developers fast, reliable tools without the privacy cost of pasting sensitive data into a random website.

Everything runs in your browser

There is no backend. Every conversion, decode, and hash happens locally in JavaScript on your own device using standard Web APIs. Your input is never sent to a server, never logged, and never stored anywhere but your own browser tab. That means you can safely decode a production JWT, hash a customer record, or format an internal API response without it leaving your machine. You can even use the tools offline once the page has loaded.

How it is built

The site is a static export built with Next.js, React, and TypeScript, served as plain HTML and JavaScript from a global CDN. There are no trackers, no analytics that fingerprint you, and no account system. The source emphasises clear, boring, well-tested code over cleverness, and each tool is a single self-contained page that loads in under a second on a cold cache.

The tools

• 📋 JSON Formatter — Format, validate and minify JSON — locally in your browser
• 🔄 Base64 Converter — Encode & decode Base64 strings — no data uploaded
• 🔗 URL Encoder — Encode & decode URLs with full UTF-8 support
• 🔑 JWT Decoder — Decode JWT tokens locally — never sent to a server
• ⏱ Timestamp — Convert Unix timestamps to dates and back instantly
• 🆔 UUID Generator — Generate cryptographically secure UUID v4 in bulk
• 🔐 Hash Generator — Calculate MD5 / SHA256 / SHA512 hashes securely
• 🔍 Regex Lab — Test & debug regular expressions with live matching