I built 150+ free developer tools that run entirely in your browser - no backend, no tracking

Dusk Tools — Wed, 11 Mar 2026 03:46:50 +0000

Every developer has that moment where they need to quickly decode a Base64 string, check what a HTTP code actually means, or test a regex expression - and ends up on some sketchy site covered in ads that's probably logging everything you paste into it.

I got tired of that. So I built DuskTools.

What it is

150+ free browser-based developer tools. No sign-up. No tracking. No backend processing your data. Everything runs locally in your browser - your data never leaves your device.

What's included

Encoding & formatting
JSON formatter / validator
Base64 encoder / decoder
URL encoder / decoder
JWT decoder
HTML entity encoder
Generators
UUID / ULID generator
Password generator
Hash generator (MD5, SHA-1, SHA-256)
CUID generator
CSS tools
Gradient generator
Box shadow builder
Border radius generator
Color converter
Reference pages (the ones I'm most proud of)
HTTP status code lookup — every code with causes, fixes, and a live URL checker embedded on each page
Port number database - common ports with copy-paste firewall commands
MIME type reference - with a drag-and-drop file detector
Linux command docs
JavaScript method reference
Regex pattern library — with a live tester on every pattern page
Cron expression presets — with a next-run-time previewer

The privacy angle

Most "free online tools" are running your data through their servers. That matters when you're decoding a JWT that contains user info, or formatting JSON from a production database.

With DuskTools, there's nothing to intercept. The processing is entirely client-side. The only exception is the HTTP status checker, which intentionally hits a server endpoint - because browsers can't fetch arbitrary URLs due to CORS.

The reference + tool fusion

The thing I think differentiates it: every reference page has an embedded tool.

Reading about HTTP 404? There's a live URL checker right on the page. Reading about a MIME type? Drop a file in and detect it. Reading about a regex pattern? Test your string against it inline.

The idea is that developer searches usually have two intents -understand something or do something — and a page that satisfies both tends to be genuinely more useful.

Tech stack
Next.js (App Router) with SSG for reference pages

That's it.

Zero external runtime dependencies for client-side tools

Try it here: https://dusktools.app

Happy to hear what tools you'd want added, or what's broken.

Built this as a side project and it's been a fun exercise in making something actually useful without any of the usual web cruft.

Cheers.

DEV Community: Dusk Tools

I built 150+ free developer tools that run entirely in your browser - no backend, no tracking