# Regular expression tester

Canonical page: https://nepocore.com/tools/regex-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.

## How to use it

1. Enter a sample value, color, URL or structured input.
2. Choose the required format or options and run the tool.
3. Review the output and copy it into your own workflow.

## Example

Find words or dates in a short log sample before using a pattern in your own code.

## Limits and checks

JavaScript regex syntax is used. Large or pathological expressions can be stopped by the time limit instead of freezing the page.

## Access and processing

Free to use without an account. Interactive processing requires JavaScript in a modern browser. Input is processed in the browser rather than sent to a processing server. Optional browser storage is not a synchronized account.


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