Utilities
Free Online Regex Tester & Debugger
Test JavaScript regex patterns live, inspect matches and capture groups, and get safe syntax errors without sending text to a server.
100% Client-Side. Your data is processed locally and is never sent to an ElDevo processing server.
Input
Output
Ctrl/Cmd + Enter to run · Esc to clear · Processing stays in your browser.
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How to Use
- 1Enter a JavaScript regex pattern.
- 2Choose the flags you need.
- 3Paste the test text.
- 4Inspect matches and capture groups.
Features & Privacy Guarantee
- ✓ Live match results
- ✓ Flags g, i, m, s, u, y
- ✓ Capture groups and indexes
- ✓ Invalid-pattern error handling
Search intent: Test JavaScript regular expressions against sample text.
Technical Example
Input
^hello
Output
Matches: hello
Frequently Asked Questions
Which regex engine is used?
The browser's native JavaScript RegExp engine is used.
Does the tool send my text to a server?
No. Matching is local to your browser.
Can I test capture groups?
Yes. Each match shows numbered and named captures when available.
Why is my regex invalid?
The browser rejects unsupported syntax or malformed patterns and the error is shown instead of crashing the page.