Regex Tester
About Regex Tester
Regular expressions (regex) are powerful patterns used to match, search, and manipulate text. Our free regex tester helps developers, data analysts, and anyone working with text to build, test, and debug their regular expressions with instant visual feedback.
This tool provides real-time matching as you type, highlighting all matches directly in your test string. You can see exactly where your pattern matches, including the index position, matched value, and any capture groups. Named capture groups are also fully supported, making it easy to extract specific parts of your matches.
The flag checkboxes let you customize how the regex engine interprets your pattern. The global (g) flag is enabled by default to find all matches. Add the case-insensitive (i) flag for flexible matching, or enable multiline (m) mode when working with text that has multiple lines. The dotall (s) flag is useful when you need the dot character to match newline characters as well.
Common regex use cases include validating email addresses, parsing log files, extracting data from text, search and replace operations, and input validation in forms. Whether you are learning regex for the first time or debugging a complex pattern, this tester provides the feedback you need to get your patterns right.