Regex Tester
Test JavaScript regular expressions in real-time. Find matches, capture groups, and validate your patterns instantly.
How to use the Regex Tester
This tool allows you to write a regular expression (regex) and immediately test it against a sample string of text. The engine runs locally in your browser using standard JavaScript regex behavior.
- Pattern: Type your regex between the forward slashes.
- Flags: Add modifiers like
g(global),i(case-insensitive), orm(multiline) after the closing slash. - Matches: Matches are highlighted in the text area and detailed in the result list below, including any capture groups.
Common Regex Flags
Without the g flag, the regex will stop at the first match it finds. With g, it will find all matches in the text.
Makes the pattern match regardless of uppercase or lowercase letters. /a/i will match both "a" and "A".
Changes the behavior of ^ and $ to match the start and end of any line within the text, rather than just the start and end of the entire string.