Regular Expression Tester
Test regex patterns against sample text. Highlight matches, inspect capture groups, and fix syntax errors.
Build and debug regular expressions against sample text. Matching runs locally using the same RegExp engine as modern browsers.
Pattern and sample text stay on your device.
Use cases
- Prototype validation rules before adding them to application code.
- Extract fields from log lines or CSV samples.
- Explain capture groups to teammates with live examples.
Frequently asked questions
Which regex flavor is supported?
JavaScript RegExp (ECMAScript). Features depend on the flags you enable, such as global or dotAll.
Why are there no matches?
Check anchors (^ $), flag case sensitivity, and whether global mode is required for multiple matches.
Can this replace static analysis?
No. It helps craft patterns; repository-wide scanning needs tools like CodeInspector.
Related tools
Find maintainability and quality issues in real codebases with CodeInspector.