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Regex Tester & Debugger

Test and debug regular expressions with real-time match highlighting, groups, and flags support.

4.9 / 5(2450 votes)
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Execution Mode
100% Client-Side In-Browser
Data Privacy
Zero Persistent Storage
Access Policy
Free · No Signup Required
//
Valid Pattern — 2 matches found

Match Details

Match #1: "support@example.com" (Index: 14)
Group 1: "support"
Group 2: "example.com"
Match #2: "info@example.com" (Index: 37)
Group 1: "info"
Group 2: "example.com"

How to Use Regex Tester & Debugger

  1. 1

    Enter your regex pattern in the pattern field.

  2. 2

    Paste your test string below.

  3. 3

    View matches highlighted in real time.

Key Features

  • Real-time match highlighting
  • Capture group display
  • Flag toggles (i, g, m, s)
  • Explanation breakdown

Benefits

  • Debug complex regex patterns instantly
  • Understand regex groups visually
  • Test patterns against sample data

Common Pitfalls to Avoid

  • Forgetting to escape special characters like `.` and `*`.
  • Not setting global flag `g` for multiple matches.

Data Handling & Privacy Notice

This utility executes entirely client-side in your web browser. No text, calculations, or uploaded data are sent to our servers or stored in any database.

Frequently Asked Questions

This tool uses JavaScript's built-in regex engine (ECMAScript standard).

Guides & Articles for Regex Tester & Debugger

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