TEST · LOCAL FIRST
Test regular expressions with immediate match results
Inspect matches and capture groups while a protected background worker limits expensive expressions.
Regex Tester Open →HOW TO USE
How to use
- 01
Enter a regular expression and flags.
- 02
Paste the text you want to test.
- 03
Review matches and capture groups, or adjust an expression that exceeds the time limit.
USE CASES
Use cases
Validate a log pattern
Check whether an expression extracts the intended values from sample logs.
Review capture groups
Inspect numbered groups before using a pattern in code.
FAQ
Frequently asked questions
Can a regular expression freeze the page?
Testing runs in a background worker with an execution limit to reduce that risk.
Which syntax is supported?
The tool follows the regular-expression features supported by your browser's JavaScript engine.