DEVELOPER TOOLS

Regex Tester

highlight matches

This tool runs a regular expression against sample text and highlights every match live as you type, along with capture group details, so you can build and debug a regex pattern without leaving your browser.

How to use the regex tester tool

  • Enter your regular expression pattern.
  • Set any flags you need (like global or case-insensitive).
  • Paste your test text into the input box.
  • Matches highlight automatically as you adjust the pattern.

When you'd use this

Debugging a regex pattern that isn't matching what you expect.

Testing a validation pattern (like an email or phone format) against sample inputs.

Extracting or checking capture groups from a pattern before using it in code.

Frequently asked questions

Which regex flavor does this use?

It uses standard JavaScript regular expression syntax, which covers the vast majority of common pattern needs.

Can I test multiple lines of text at once?

Yes — paste a full block of multi-line text and, with the appropriate flags enabled, matches across the whole block are highlighted.

About this tool

ToolBench runs this tool entirely in your browser. Your file or text is processed on your own device using JavaScript — nothing is uploaded to a server, nothing is stored, and there's no sign-up wall between you and the result. That's true of every one of the 500+ tools on this site, from PDF utilities to unit converters.

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