Regex Tester

Developer

Test and debug regular expressions with live match preview. All processing happens locally in your browser.

Regular Expression

//g

0 / 1000 characters

Flags

Test Text

0 / 50,000 characters

Your regex pattern and test text are processed in your browser and are not sent to any server. Inputs are limited to prevent browser performance issues.

Results

Enter a pattern above to start matching.

How to Use

1Enter a regular expression pattern in the pattern field.
2Select the flags you need: g (global), i (case insensitive), m (multiline), and more.
3Paste or type the text you want to test in the test text area.
4Matches are highlighted in the preview as you type, with no button click required.
5Review match details including position, value, and capture groups.
6Use Load Sample to try a built-in date pattern example.

Common Use Cases

Validate email addresses, phone numbers, or URLs

Extract specific data patterns from logs or documents

Find and replace text using capture groups

Debug complex regular expressions step by step

Test patterns for use in JavaScript, Python, or other languages

Learn regular expression syntax with live feedback

Frequently Asked Questions

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