Regex Tester Tool
Test and debug your regular expressions (regex) with our powerful regex tester tool. Features real-time matching, syntax highlighting, and detailed match information for efficient pattern development.
Max file size: 5MB. You can also paste text directly in the input box above.
About Regex Tester Tool
Our Regex Tester Tool is a comprehensive solution for testing, debugging, and validating regular expressions. With real-time pattern matching and detailed match information, it helps developers and text processing professionals perfect their regex patterns for any use case.
- Real-time pattern matching with instant feedback
- Support for all regex flags (g, i, m, s, u, y)
- Detailed match information including position and groups
- Line and column numbers for precise match locations
- Syntax highlighting for better pattern readability
- Export functionality for match results
- Common regex pattern templates
- Support for large text inputs
How It Works
1. Enter Your Pattern
Type your regular expression pattern in the pattern input field. The tool automatically validates your pattern and shows any syntax errors in real-time.
2. Configure Options
Select the appropriate regex flags (global, case-insensitive, multiline, etc.) to modify how the pattern matching behaves.
3. Input Test Text
Enter or paste your test text in the input area. You can also upload text files or use predefined templates for common patterns.
4. Analyze Results
View detailed information about each match, including the matched text, position, line numbers, and captured groups. Export results for further analysis.
Frequently Asked Questions
What are regex flags and how do they work?
Regex flags modify how pattern matching behaves. Common flags include "g" (global) for finding all matches, "i" (case-insensitive) for ignoring case, "m" (multiline) for multi-line matching, and "s" (dotAll) for allowing dots to match newlines.
How can I use captured groups in my regex?
Use parentheses () to create captured groups in your pattern. For named groups, use the syntax (?<name>pattern). The tool will display all captured groups in the match results, making it easy to extract specific parts of your matches.
Can I save or export my match results?
Yes, you can export match results in various formats. Use the download button to save all matches or unique matches to a text file. The exported file includes the matched text, positions, and any captured groups.
Is there a size limit for the input text?
The tool can handle up to 50,000 characters in the test string and 1,000 characters in the pattern. For larger inputs, consider processing the text in smaller chunks or using the file upload feature to process text files.
How do I use the pattern templates?
Click the "Load Template" button to access a library of common regex patterns. These include patterns for email validation, URL matching, date formats, and more. Select a template to automatically populate the pattern field with a tested regex pattern.