A regular expression (regex) is a sequence of characters that defines a search pattern. It is used for pattern matching within strings, allowing you to search, validate, and manipulate text.

g (global) finds all matches, not just the first. i (case-insensitive) ignores letter case. m (multiline) treats ^ and $ as matching the start/end of each line, not just the entire string.

Enter your regex pattern, select appropriate flags, then paste your test string. Matches will be highlighted in yellow, and match details will be shown below.

Yes! Use parentheses () to create capture groups. The tool will display captured groups for each match in the results section.