Web & Dev
The reference material and quick checks that come up while building for the web. The regex tester runs your pattern inside a worker with a hard timeout, so a catastrophically backtracking expression cannot freeze the tab — a failure mode most online testers still have.
5 tools in this category.
Color Converter Convert colors between HEX, RGB, HSL, HWB, OKLCH and CMYK with a live contrast check. CSS Minifier Minify CSS safely, preserving strings, custom properties and licence comments. HTTP Status Code Lookup Search every HTTP status code with its meaning, typical cause and correct usage. Regex Tester Test regular expressions with highlighted matches, capture groups and a safety timeout. User Agent Parser Break a user agent string into browser, engine, operating system and device.