How to Use Regex Tester

Use the Regex Tester tool

This guide walks you through using Regex Tester effectively. Test regular expressions with real-time matching, syntax highlighting, and cheat sheet. All processing happens in your browser — your data never leaves your device.

How to Use Regex Tester

01Live Matching

See regex matches highlight in real-time as you type your pattern and test string.

02Flags Support

Toggle global, case-insensitive, multiline, dotall, unicode, and sticky flags.

03Match Details

View each match's index, groups, and capture group values.

04Replace Tool

Test regex replacements live before using in code.

05Debugging and testing regular expressions before deploying to production code

Debugging and testing regular expressions before deploying to production code

06Validating input patterns like email, phone, and postal code formats

Validating input patterns like email, phone, and postal code formats

07Extracting structured data from unstructured text using capture groups

Extracting structured data from unstructured text using capture groups

Frequently Asked Questions

Is Regex Tester free to use?

Yes, Regex Tester is completely free with no sign-up required, no usage limits, and no hidden fees.

Does Regex Tester upload my data?

No. All processing happens locally in your browser. Your data never leaves your computer.

Try the Tool

Regex Tester

Test regular expressions with real-time matching, syntax highlighting, and cheat sheet.

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