Regex Tester — Free Online Tool
Write a pattern, paste your text and watch every match highlight live — with match positions and captured groups broken down for you.
Type a pattern and some test text above — the matches will appear here.
Highlight Matches in text
Details Match list
Live results as you type
No sign-up needed
Free forever
How it works
1Type your pattern (or pick a common one) and toggle the flags.
2Paste your test text — matches highlight live as you type.
3Inspect the match list for each match's index and captured groups.
Frequently asked questions
Is my test text uploaded anywhere?
No. The pattern is compiled and tested with your browser's built-in JavaScript RegExp engine, so everything stays on this page — nothing is uploaded or stored.
What do the g, i, m, s and u flags do?
g (global) finds all matches instead of just the first; i makes matching case-insensitive; m lets ^ and $ match at line boundaries; s lets the dot match newlines too; u enables full Unicode mode.
What does the match list show?
Every match with its character index in the test string, plus each captured group from parentheses — so you can see exactly what your groups captured.
JavaScript regex syntax · live highlighting · 100% local — your text never leaves this page.