Regex tester online
Free online regex tester. Test regular expressions with match highlighting, capture groups and customizable flags in real time.
//g
How it works
Write the regular expression in the pattern field, enter test text and matches are highlighted in green in real time. You can toggle flags g (global), i (case-insensitive), m (multiline) and s (dotAll).
FAQ
What is a regular expression?
A regular expression (regex) is a search pattern used to find, validate or replace text. For example \d+ finds all numbers in a text.
What do the flags mean?
g = find all matches (not just the first), i = ignore case, m = ^ and $ work per line, s = dot . includes line breaks.
What are capture groups?
Parentheses () create capture groups that extract specific parts of the match. For example (\w+)@(\w+) captures user and domain separately from an email.
