Regex Tester

Test regular expressions with live pattern matching and highlighting

Enter your regex pattern without delimiters (e.g., \d{3}-\d{3}-\d{4})
The regex will be tested against this text and matches will be highlighted

How to Use Regex Tester

1

Enter Regex Pattern

Type your regular expression pattern in the first field. Use standard regex syntax with support for all common patterns.
2

Enter Test String

Paste or type the text you want to test against your regex pattern in the second field.
3

Select Flags

Choose regex flags (global, case-insensitive, multiline) if needed. Then click "Test" to run the pattern matching.
4

View Matches

See all matches highlighted in your test string. The tool shows match count, matched text, and position information.

About Regex Tester

The Regex Tester is a powerful tool for developers who work with regular expressions. It provides real-time pattern matching, syntax highlighting, and detailed match information to help you build, test, and debug regex patterns quickly.

Key Features:

  • Live Pattern Matching: See matches highlighted as you type
  • Flag Support: Global (g), case-insensitive (i), and multiline (m) flags
  • Match Details: Shows all matches with positions and captured groups
  • Syntax Highlighting: Visual feedback for your regex pattern
  • Error Detection: Identifies invalid regex syntax with clear messages

Perfect For:

  • Building and testing regex patterns for validation
  • Debugging complex regular expressions
  • Learning regex syntax through experimentation
  • Extracting data from text using pattern matching
  • Validating regex before implementing in code