Regex Tester
Real-time testing of regular expression matching effects, supports multi-line text and various matching modes
Match Results
Common Regular Expression Examples
Email Address
^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$
Phone Number
^1[3-9]\d{9}$
ID Card
^\d{17}[\dXx]$
IP Address
^(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)$
How To Test A Regular Expression
Paste your regular expression into the pattern field, add sample text, choose the flags you want to test, and review the highlighted matches. A good regex test includes both values that should match and values that should not match. This makes it easier to catch patterns that are too broad, too strict, or missing an important edge case.
The tester is especially useful when debugging extraction patterns for logs, CSV-like text, URLs, dates, emails, IDs, and user-generated input. It lets you see how global, case-insensitive, and multiline matching changes the result before you paste the expression into application code.
Testing Checklist
Start with anchors if the whole value must match, such as a form field. Remove anchors if you are searching inside longer text. Add a few invalid examples so you can detect false positives. If a match is unexpectedly missing, check escaping, whitespace, line breaks, and whether the regex engine supports the syntax you used.
Regex Tester FAQ
What does the global flag do? The global flag finds every match instead of stopping after the first one.
When should I use multiline mode? Use multiline mode when `^` and `$` should match the start and end of each line rather than only the start and end of the full text.
Can I test generated patterns here? Yes. Generate a first draft in the Regex Generator, then test it here with realistic examples and edge cases.