RetroBox – 50+ In-Browser Dev & Design Tools

by gmennegaut@gmail.com · Developer Tools

Manifest V3 Free

View in Chrome Web Store Data as of 16 Oct 2026

Fast, 100% private developer & designer tools right in your browser. JSON Formatter, JWT, Eyedropper, Crypto, and 50+ utilities.

Users

+9 in 30 days

Rating

5.0 / 5

+5.00 in 30 days

Ratings

+2 in 30 days

Store rank

#192K

#161K among extensions

Version

1.0.0

updated 2 Sep 2026

Users

monthly, 1 months

Latest, 16 Oct 2026: 10 usersMove the mouse over the chart for any month

Ratings count

monthly, 1 months

Latest, 16 Oct 2026: 2 ratingsMove the mouse over the chart for any month

The Chrome Web Store rounds user counts down to the leading digit, so the user line moves in steps. The ratings count is exact and is the better signal of real adoption.

About RetroBox – 50+ In-Browser Dev & Design Tools

RetroBox is a privacy-first browser extension designed for web developers, designers, and software engineers. It provides quick access to client-side utilities directly within your browser popup and Chrome side panel. All processing runs 100% locally on your device using browser APIs, with zero data transmitted to remote servers. Key Features: - Format, validate, and minify JSON data with custom indentation. - Decode JWT tokens and inspect headers, payload claims, and expiration dates. - Test regular expressions live with instant match highlighting. - Generate secure cryptographic passwords and UUID v4 identifiers. - Encode and decode text to Base64 or URL formats. - Convert Unix epoch timestamps to readable date formats. - Convert cURL requests to JavaScript fetch code. - Quick text case conversion for common programming conventions. - Calculate SHA-256 and SHA-512 cryptographic hashes. - Includes a persistent local scratchpad for quick notes and code snippets.