How to use regular expression tester
Test a JavaScript regular expression against sample text and inspect matches and capture groups. Pattern matching runs in a worker with a time limit.
- Enter a sample value, color, URL or structured input.
- Choose the required format or options and run the tool.
- Review the output and copy it into your own workflow.
Try this next
Find words or dates in a short log sample before using a pattern in your own code.
JavaScript regex syntax is used. Large or pathological expressions can be stopped by the time limit instead of freezing the page.
Questions, answered.
Is regular expression tester free to use?
Yes. This tool is part of Nepocore’s free browser toolkit. There is no paid tier, file-download gate or application account required.
What should I check before using the result?
JavaScript regex syntax is used. Large or pathological expressions can be stopped by the time limit instead of freezing the page.
Does this tool upload my files or text?
The tool processes its input in your browser. File contents and text are not sent to a processing server. See the privacy page for local storage and hosting details.