Enter a regex pattern above to start matching
About Regex Tester
Regex Tester is an interactive editor to write, test, and optimize regular expressions. It provides live visual match feedback on your test string and explains matches step-by-step.
How to Use Regex Tester
- Enter your regex pattern in the pattern box.
- Choose flags like global (g), case-insensitive (i), or multiline (m).
- Type or paste your test text.
- See matches and capture groups highlighted in real-time.
Frequently Asked Questions
What is a Regular Expression?
A regular expression (regex) is a sequence of characters defining a search pattern, used for string matching, search-and-replace, and input validation.
Which regex engine does this test?
It uses the native JavaScript regex engine (ECMAScript specification) running directly inside your browser.
Does this tool save my regex patterns?
No, all computations are computed inside your local browser memory, keeping your regex patterns and test values private.