text Tools
Regex Tester
Test regular expressions with live highlighting and match results.
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Buy me a coffeeWhat is Regex Tester?
Regular expressions (regex) are powerful patterns used for matching, searching, and manipulating text. This tool helps you test and debug your regex patterns with live highlighting, showing all matches and capture groups in real-time. Perfect for learning regex or validating patterns.
How to Use Regex Tester
1. Enter your regex pattern (without slashes)
2. Select flags (g, i, m, etc.)
3. Enter test text to match against
4. See matches highlighted and listed below
5. View capture groups for each match
Common Use Cases
- Testing patterns for form validation
- Building search and replace patterns
- Extracting data from text
- Validating email, phone, or URL formats
- Learning regular expression syntax
Frequently Asked Questions
What do the flags mean?
g = global (find all matches), i = case-insensitive, m = multiline (^ and $ match line starts/ends), s = dotAll (. matches newlines)
Why is my regex not matching?
Common issues: forgetting the global flag for multiple matches, escaping special characters, or case sensitivity. Check your flags and escape \ characters properly.
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