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Online Regex Tester

Test and debug your regular expressions in real-time with syntax highlighting and detailed match information.

How to Use This Tool

This interactive regex tester allows you to experiment with regular expressions and see immediate results. Follow these steps:

  1. Enter your pattern: Type your regular expression in the pattern field. The tool supports all standard JavaScript regex syntax.
  2. Select flags: Choose appropriate flags:
    • g (Global): Find all matches in the text
    • i (Case Insensitive): Match both uppercase and lowercase letters
    • m (Multiline): Treat ^ and $ as matching the start/end of each line
  3. Enter test text: Paste or type the text you want to search through.
  4. View results: The tool will highlight all matches and show detailed information including match position and capture groups.
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Why Use an Online Regex Tester?

Instant Feedback

See matches update in real-time as you type. This immediate feedback loop helps you learn and debug faster than running code repeatedly.

Visual Debugging

Our tool highlights matches and captures groups visually, making it easier to understand exactly what your pattern is matching (and what it's missing).

Cross-Platform

Works right in your browser. No need to install IDE plugins or command-line tools. Access your regex environment from anywhere.

Safe Experimentation

Test complex patterns on sample data without risking production code or data integrity.

🔥

Popular Patterns

📧

Email Address

Validate standard email formats. Includes support for common domains and subdomains.

Try Email Regex →
📅

Dates (YYYY-MM-DD)

Match dates in ISO 8601 format. Validates year, month, and day structure.

Try Date Regex →
📱

US Phone Number

Match various US phone formats including dashes, dots, and parentheses.

Try Phone Regex →
🌐

IPv4 Address

Validate IPv4 addresses with proper range checking (0-255).

Try IP Regex →
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