Regex Tester
Test JavaScript regular expressions with match positions and capture groups.
Runs on your device. Files are never uploaded.Good to know: Badly written patterns can run for a very long time on large inputs (catastrophic backtracking) and freeze this tab. Reload if that happens.
How to use Regex Tester
- Enter the pattern and flags
- Paste test text
- Read the matches
About this tool
Type a pattern and flags, paste sample text, and see every match with its index, line number, numbered groups and named groups.
Like every tool on YantraStack, it is free with no accounts, limits or watermarks, and it works offline once the page has loaded. See how to verify that nothing is uploaded.
Questions
Which regex flavour is this?
JavaScript (ECMAScript). Lookbehind and named groups are supported by modern browsers.
Guides
How to convert text to camelCase, snake_case, kebab-case and more
Switch between UPPER, lower, Title, Sentence, camel, Pascal, snake, kebab, dot.case, Train-Case, URL slugs and more with one paste.
How to test a regular expression online (JavaScript regex)
Enter a pattern and flags, paste sample text and see every match, its position and capture groups. Includes useful patterns and common pitfalls.