Regex Tester
Test, debug, and validate regular expression patterns with live visual highlighting.
| Match # | Full Match | Group(s) |
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How to Use the Regex Tester
Follow these simple steps to use this tool directly in your browser.
Enter Regex Pattern
Type your regular expression pattern and flags (e.g. g, i, m).
Input Test String
Paste the text you wish to match and validate against.
Review Matches
See matching substrings highlighted live in the text preview and capture groups detailed below.
Key Features
Real-Time Visual Highlighting
Colorizes matched substrings as you type your pattern.
Capture Group Table
Extracts individual capture groups into an easy-to-read table.
Regular expressions (regex) are formal strings defining search patterns used for string validation, parsing, and text transformations. Our interactive tester lets you test regex syntax directly against sample input without executing shell scripts.
Frequently Asked Questions
It utilizes the native ECMAScript JavaScript regex engine built into your web browser.
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