Regex Tester
Developer Tools
Test regular expressions
How to Use
- 1. Enter your regex pattern in the pattern field
- 2. Select the appropriate flags (global, case insensitive, etc.)
- 3. Enter the text you want to test against
- 4. Click "Test Regex" to see all matches
Example / Use Case
Test Email Validation Pattern
A developer builds a registration form and needs to validate email addresses. They use the Regex Tester to verify their email pattern works correctly.
Input
Regex: ^[w.-]+@[w.-]+.w+$ Test: user@example.com
Output
✅ Match Found! Matches: user@example.com
How It Works
Regular expressions (regex) are patterns used to match character combinations in strings. They are powerful tools for text validation, search and replace operations, and data extraction. The regex tester allows you to enter a pattern and test string to see matches in real-time.
Common uses include validating email addresses, phone numbers, passwords, and other form inputs. Regex can also extract specific data from text, like finding all URLs or emails in a document. The tester shows exactly what matches and highlights capture groups for extraction.
Key regex syntax: . matches any character, * matches zero or more, + matches one or more, ? makes something optional, [] defines character classes, and () creates capture groups.
How to Use
- 1Enter your regular expression pattern in the regex field
- 2Enter test string to match against in the text area
- 3View matches highlighted in real-time
- 4See captured groups displayed below the match
Frequently Asked Questions
The tester uses JavaScript regex flavor, which is the most common for web development.