About Regex Tester
Write and test regular expressions against sample text in real time, with all matches and capture groups highlighted. Supports flags like global, case-insensitive, and multiline. See match counts, group contents, and positions as you type — ideal for building and debugging regex patterns without trial and error in code.
How to Use Regex Tester
- 1
Enter your regex
Type your regular expression pattern in the regex input field.
- 2
Add test text
Paste or type the text you want to match against in the test input.
- 3
Review matches
See all matches highlighted in real time with group details shown below.
Common Use Cases
- Validating input formats like emails and phone numbers
- Extracting data patterns from large text blocks
- Building search-and-replace logic for code editors
- Testing regex patterns before adding them to production code
Frequently Asked Questions
What regex flavor does this tool use?
Can I test capture groups?
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