Test Regular Expressions against text in real time, view captured groups, and see a visual token breakdown.
A developer utility for writing, testing, and understanding Regular Expressions. Highlight pattern matches instantly and inspect captured groups.
Enter your Regular Expression pattern and select flags (e.g. g, i, m).
Paste your sample test text into the test string box.
View live highlighted matches and captured match groups.
Use preset regex patterns for emails, URLs, dates, or phone numbers.
Real-time pattern matching with color-coded highlight overlays
Support for global (g), case-insensitive (i), and multiline (m) regex flags
Match detail inspector showing match indices and capture groups
Pre-built regex library for quick testing
Browser-based pattern evaluation with immediate feedback
Input
Pattern: [a-z0-9._%+-]+@[a-z0-9.-]+\.[a-z]{2,} | Text: user@example.comOutput
Match found: user@example.com
Regex Tester & Visual Token Explainer transforms, validates or analyzes the data you provide according to the operation described on this page. The output should be reviewed before it is used in production code or security-sensitive workflows.
Generated or transformed output should be reviewed before deployment. Do not paste secrets, private keys, passwords or other sensitive credentials into a tool unless its privacy behavior explicitly supports that use.
This tool is designed to perform its main calculation or transformation in your browser. Do not enter information that the tool does not need, and review the site's Privacy Policy for analytics, advertising and third-party services.
Answers about how the tool works, its limitations, and how your information is handled.
The tool supports standard JavaScript regex flags including 'g' (global), 'i' (case-insensitive), and 'm' (multiline).
No. All regular expression evaluations happen locally inside your browser runtime.
This tool is designed to perform its main calculation or transformation in your browser. Do not enter information that the tool does not need, and review the site's Privacy Policy for analytics, advertising and third-party services.
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