Regex Tester
Test regular expressions against sample text with live match highlighting.
Overview
About the Regex Tester
Build and debug regular expressions with instant feedback. Enter your pattern and test string to see matches highlighted, groups extracted and errors explained — all without leaving your browser.
Benefits
How it works
- 1Enter your regular expression pattern in the input field.
- 2Paste or type the text you want to test against.
- 3Toggle flags such as global, case-insensitive and multiline.
- 4Review matches, capture groups and any syntax errors in real time.
Applications
Use cases
- Validate form input patterns before deploying to production.
- Extract structured data from logs and unstructured text.
- Debug complex regex used in search-and-replace workflows.
- Learn regex syntax by experimenting with live examples.
Support
Frequently asked questions
Which regex flavor is supported?
Can I test capture groups?
Why does my pattern show an error?
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