Regular Expression Tester - My Tools

• Regular expression pattern: Enter the pattern to test.
• If needed, select the i, m, and s flags.
• Enter the test string to see match positions and the count in the real-time preview.
• Test matches: Click it to view detailed server-side matching results in JSON format.

A regular expression is an expression used to find, test, and replace specific patterns in strings.

This tool shows both a browser-based real-time preview using new RegExp() and the server-side Python re matching results.

It is useful for quickly validating recurring text rules such as numbers, email addresses, dates, and log patterns.