Regex Tester
Test regular expressions instantly with live matches, flags, capture groups, and replace mode. Debug patterns quickly for validation, parsing, search, and text transformation workflows.
Regex Controls
Enter a regex pattern, turn flags on or off, test against text, and optionally preview replacements.
Enter only the pattern, not surrounding slashes.
Flags
Quick sample patterns
Contact us at support@smarttools.co.in or sales@example.com. Backup email: hello.world+test@sample.org
Status
Regex compiled successfully.
Matches
3
Replace mode
Off
Pattern length
41
Text length
102
Match details
Inspect each match, its position, and capture groups.
Match #1
Start: 14 · End: 38
support@smarttools.co.in
Match #2
Start: 42 · End: 59
sales@example.com
Match #3
Start: 75 · End: 102
hello.world+test@sample.org
Included features
- Pattern testing with common regex flags.
- Live highlighted matches with exact positions.
- Capture group inspection for each match.
- Optional replace mode with preview and export.
- Text file upload, copy, and download support.
- Ready-to-use sample patterns for common tasks.
What can this regex tester do?
This tool lets you test regex patterns against sample text, turn flags on or off, inspect matches and groups, preview replacements, and upload text files for fast debugging.
Common use cases
Use it for email checks, URL parsing, log scanning, data extraction, string validation, text cleanup, coding interviews, and general regular expression debugging.