Regex Tester & Validator
Test, validate and match regular expressions
Test, validate and match regular expressions
In PCRE2, '{,3}' with an omitted minimum is not a valid quantifier, so this pattern matches the literal five-character string 'a{,3}' (or 'A{,3}' with the case-insensitive flag). This is a common portability gotcha: unlike Python or POSIX ERE, PCRE2 requires the explicit 'a{0,3}' form to match zero to three 'a' characters. The global flag finds all occurrences, while multiline has no effect here.