Regex tester
Write a regular expression, test it against sample text, inspect matches and capture groups, and preview replacement output directly in your browser.
0 of 200000 characters
Matches
Regex testing runs on your device. Patterns, sample text, and results are not uploaded or stored.
Check patterns before using them
Regular expressions are powerful, but small mistakes can change what gets matched. Testing a pattern with real sample text helps you confirm the exact text range, match count, and capture groups before using it in a script, editor, or data cleanup task.
The tester keeps flags visible so case sensitivity, multiline matching, dot behavior, and Unicode mode are easier to reason about. Matches are highlighted in the original text, and the list below shows positions and captured groups for closer inspection.
Replacement preview is optional. Add a replacement value when you want to check a rename, cleanup, or formatting rule. All text is processed in the browser, so private samples and internal snippets are not uploaded.
Related tools
Continue with tools that fit the same task flow.