Test a regular expression against your text in real time. See every match highlighted, with capture groups and flags. Runs entirely in your browser.
How to use the Regex Tester
Type your regular expression in the pattern field.
Toggle the flags (g, i, m, s, u) you need.
Enter the test string and see matches highlighted with their groups.
Frequently asked questions
It uses your browser's JavaScript (ECMAScript) regular-expression engine, so the syntax matches what you would use in JavaScript and TypeScript.
g finds all matches, i is case-insensitive, m makes ^ and $ match line starts and ends, s lets the dot match newlines, and u enables full unicode mode.
Yes. Each match lists its numbered groups, and named groups are captured too. Matches are highlighted in the test string so you can see exactly what was matched.
No. The pattern runs against your text entirely in your browser; nothing you type is sent anywhere.
This regex tester runs a regular expression against your text and highlights every match as you type, using your browser's JavaScript regex engine. It lists matches with their position and capture groups.
It is built for developers writing and debugging patterns for validation, search and parsing. Everything runs locally, so your patterns and data stay private.
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