Regex tester — test patterns with live matches
Type a regular expression and a test string and see every match and capture group instantly. It runs entirely in your browser (0 uploads, works offline).
How to use it
- Enter your pattern and flags.
- Paste the text to test against.
- Read the matches and captured groups; Copy or Download them.
FAQ
How do I test a regular expression for free?
Enter the pattern, choose flags like g and i, and paste your text. This page lists every match with its position and capture groups, updating live — on your device with no upload.
Which regex flavour does it use?
JavaScript's regular-expression engine, so patterns behave exactly as they will in the browser or Node. Flags such as global, ignore-case, multiline and dotall are supported.
Is my text uploaded anywhere?
No. Matching runs entirely in your browser and nothing is transmitted or stored, which you can verify by turning off your Wi-Fi.
What happens if my pattern is invalid?
It shows the error message instead of crashing, so you can fix the pattern and try again immediately.
Limits
Uses the JavaScript regex engine; patterns written for PCRE or other flavours may behave differently.
Related
The regex cheatsheet explains the syntax; the text extractor pulls matches from bulk text.
Bookmark this page (Ctrl+D, or ⌘D on Mac) or install the app — it works offline the next time you need it.