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Regex Tester

🔍 Build, test, and debug regular expressions in seconds! Paste your text, adjust flags, and see matches instantly. ✨

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Real-time Testing

Instant pattern matching with live results, highlighted matches, and detailed capture group information

Flag Support

Complete regex flag support including global, case-insensitive, multiline, and advanced options

Quick Examples

Pre-built patterns for common use cases like emails, phone numbers, and color codes

Regex Tester

Regular expressions are powerful for searching, replacing, and validating text. Our Regex Tester lets you write patterns, add flags, and instantly view matches with highlighted results—all running locally in your browser.

Key Features:

  • Instant Results: Matches and captured groups update as you type – no refresh needed.
  • Comprehensive Flag Support: Global /g Case-insensitive /i Multiline /m and more.
  • Smart Highlighting: Preview pane shows every match wrapped in a yellow marker so you can spot them quickly.
  • Example Presets: One-click buttons instantly load sample patterns such as E-mail addresses, Hex colors, or phone numbers to help beginners get started.
  • Clipboard & Export: Copy individual matches or the entire match list with a single click.
  • Privacy First: All processing happens locally in your browser – nothing is sent to a server.

Usage Examples:

Validate Email Addresses

^(\w+[.-]?)*\w+@\w+([.-]?\w+)*(\.\w{2,3})+$

Matches most standard email formats, e.g. john.doe@example.com.

Extract Hex Color Codes

#?([A-Fa-f0-9]{6}|[A-Fa-f0-9]{3})

Captures 3- or 6-digit hex colors like #ff5733 or #123.

Match US Phone Numbers

^(\(\d{3}\)|\d{3})[- ]?\d{3}[- ]?\d{4}$

Accepts formats like (123) 456-7890 or 555-123-4567.

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