Regex Tester

Professional online regex testing tool. Real-time match highlighting, multiple flag support, built-in common regex templates to help developers quickly validate and debug regular expressions.

Flags:

Common Regex Examples

What You Can Do With It?

Validate Form Input Rules

Test email, phone, or ID regexes to ensure frontend validation logic is correct

Extract Text from Logs

Use capture groups to pull key data from logs or raw text dumps

Preview Replacement Rules

See replacement results live before writing the pattern into your codebase

Debug Complex Patterns

Real-time match highlighting helps pinpoint greedy, grouping, or boundary issues

Practice Regex Syntax

Work through examples against live text to understand metacharacters and quantifiers

Clean Web Scraping Data

Use regex to extract structured fields from scraped pages and filter out noise

How To Use?

1

Enter Your Regex

Type the regular expression in the regex field with optional flags

2

Paste Test Text

Paste content into the text area — matches are highlighted automatically

3

Review Match Results

See all matches and capture groups to confirm your regex logic is correct

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Frequently Asked Questions

Supports g (global), i (case-insensitive), m (multiline), and s (dotAll, makes . match newlines) - all standard JavaScript regex flags.

Encountered other problems or suggestions? Have a bug or suggestion? Drop us an email.

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Regex Tester in 2026 — A Productivity Multiplier for Developers

Regular expressions are the Swiss Army knife of text processing, supported by virtually every programming language. From form validation and log analysis to data cleaning, regex is used everywhere. Yet writing correct regular expressions is notoriously difficult — a tiny syntax difference can produce drastically different matching results.

In 2026, with the explosive growth of data processing needs, being able to quickly write and verify regular expressions has become more important than ever. Repeatedly running code in an IDE to test regex is not only inefficient but also makes it easy to miss edge cases. A real-time regex tester lets you debug expressions with instant visual feedback, significantly shortening your development cycle.

MeTool's Regex Tester provides real-time match highlighting, comprehensive flag support, and a built-in library of common patterns. Watch matching results update live as you type, iterating rapidly until you achieve the exact pattern you need.

Key Features of MeTool Regex Tester

Real-Time Match Highlighting

After entering a regex pattern and test text, all matches are highlighted in real time within the text. You can visually see exactly what is matched and what is missed — no code execution required.

Flexible Flag Controls

Supports g (global), i (case-insensitive), m (multiline), and s (dotAll) flags with simple toggle switches. Easily experiment with different flag combinations to explore how they affect matching behavior.

Built-In Common Patterns

Includes a library of pre-built patterns for email addresses, phone numbers, URLs, IP addresses, and more. Use these tested patterns as starting points, saving the time of writing regex from scratch.

Match Groups & Capture Details

Displays detailed information for each match, including the full match and all capture group contents. This is invaluable for scenarios where you use groups to extract structured data — such as parsing timestamps and error codes from log entries.

How to Test Regular Expressions with MeTool

  1. Open the Tool: Navigate to MeTool's Regex Tester page — no installation or signup needed, works directly in your browser.
  2. Enter Your Regex: Type your regular expression in the pattern input field and enable the flags you need (g, i, m, s).
  3. Enter Test Text: Paste or type the text you want to match against. Matches are highlighted in real time as you type.
  4. Analyze Results: Review the highlighted matches and capture group details. Adjust your regex pattern based on the results until it meets your requirements.