Regex Tester & Debugger
Description
Regular Expressions (Regex) are incredibly powerful but notoriously difficult to master. The Regex Tester & Debugger is a sandbox environment where you can prototype and verify your patterns before deploying them to production. It provides real-time highlighting of matches within your test string, allowing you to visually see exactly what your pattern is catching. With support for standard flags like Global, Case-Insensitive, and Multiline, it simulates a real JavaScript regex environment perfectly.
What It Does
Tests Regular Expression patterns against a sample string and highlights matches in real-time.
How To Use
- Pattern: Enter your regex in the top bar (e.g.,
[a-z]+). - Flags: Toggle flags like
g(Global) ori(Insensitive) on the right. - Test String: Paste your sample text below. Matches are highlighted instantly in green.
Who It Is For
Software engineers, data scrapers, and QA testers validating input constraints.
Freqently Asked Questions
Which flavor is this?
This tool uses the JavaScript RegExp engine. It supports modern features like lookaheads and capture groups supported by your browser.
Why isn't it matching?
Check your flags! If you want to match multiple occurrences, you must enable the g (Global) flag.
How do I match a dot?
The dot . is a special character meaning "any character". To match a literal dot, escape
it with a backslash: \.