Regex Tester

Test regular expressions with real-time matching and highlighting.

Runs entirely in your browserNo file uploadsPrivacy-first
TL;DR

Enter a regex pattern and test text to see matches highlighted in real-time. Supports flags like global, case-insensitive, and multiline. Everything runs in your browser.

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Matches will be highlighted here...

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What is Regex Tester?

Regex Tester is a tool for testing and debugging regular expressions. It shows matches highlighted in your test text and displays captured groups, making it easy to build and verify regex patterns.

When Should You Use This Tool?

Use this tool when writing regex patterns for validation, text extraction, or search/replace operations. Great for debugging complex patterns.

How to Use Regex Tester

  1. 1Enter your regex pattern in the pattern field.
  2. 2Select flags (global, case-insensitive, multiline).
  3. 3Enter test text to match against.
  4. 4See matches highlighted in real-time.
  5. 5View captured groups for each match.

How Does This Tool Work?

This tool creates a JavaScript RegExp object from your pattern and tests it against the input text. Matches are highlighted and groups are extracted using exec().

Privacy Note: Runs entirely in your browser. Your data never leaves your device. No file uploads to any server.

Common Use Cases

Developers

Build and test validation patterns.

Data Engineers

Create patterns for text extraction.

QA Engineers

Verify regex in test cases.

Frequently Asked Questions

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