Regex Tester Tool

Real-time regex testing (supports g / i / m). Input expression and text to see highlighted matches and counts.
Local + Cloud Processing
Fast & Efficient
Developer Tool

Core work may run in your browser, while optional network or AI actions transmit the input needed to provide the requested result. Review data-processing details.

AI Assistant Tip

Free users are limited to 30 uses per day.

正则表达式

测试文本

匹配结果

No Match
AI Enhancements

How to test Regex?

  • 1Enter your regular expression in the top input box (without surrounding slashes).
  • 2Select flags like g (global) or i (case-insensitive) on the right.
  • 3Type your test string into the textarea.
  • 4Matching results will be highlighted in real-time below.

Regex FAQ

What regex engine is used?

This tool uses the native JavaScript RegExp engine, which is standard in all modern browsers.

What do the g, i, m flags do?

g enables global search; i makes the matching case-insensitive; m allows ^ and $ to match start/end of lines.

Practical Regex Scenarios

  • Input Validation: Test patterns for email, phone numbers, and custom formatted IDs.
  • Data Extraction: Verify logic for pulling URLs, dates, or IP addresses from messy logs.
  • Code Auditing: Debug complex patterns used for static analysis or content replacement.
  • Data Scrubbing: Test search-and-replace or split logic on small samples before large-scale processing.

Technical Details: JavaScript Regex Engine

This tool uses your browser's JavaScript regular expression engine. Results generally match modern JavaScript environments, but supported features and behavior can vary by browser or runtime. Optional AI explanations send the pattern to our cloud AI service.