A result in three steps
- 01
Enter sample text.
- 02
Provide the regex pattern and flags.
- 03
Review matches and refine the pattern.
11
Data & developer
Regex Tester
Runs a regular expression against sample text and lists match count, positions, and capture groups. Input size is limited to reduce accidental browser freezes.
✓ Free✓ No account✓ In-browser
Result
Your result will appear here.
When is this tool useful?
- ✓ Validation patterns
- ✓ Log parsing
- ✓ Search-and-replace preparation
Important limitation
Automated output is a preliminary assessment. Do not use it alone for legal, financial, medical, or security-critical decisions.
ABOUT THIS TOOL
Frequently asked questions
Does this tool send input to a server?+
No. Processing runs in this browser tab. Data leaves the page only when you choose to copy or download the result.
Is the result definitive?+
The tool produces consistent output from disclosed rules and browser APIs, but context, data quality, and method limitations can affect it. Verify high-impact decisions.
Is input saved?+
No. Tool input is not persisted to localStorage or another durable store. Only a non-sensitive tool-usage count may be kept on this device for personalized home-page shortcuts.