Regex Editor & Tester

Matches a line beginning with an optional '+' followed by 10 to 15 characters that may be digits, whitespace, or question marks. Intended for Slovak and Czech phone numbers in international format, such as +421 901 234 567 or +420 123 456 789. The 'm' flag makes '^' anchor each line in multi-line text, while the permissive character class tolerates spaces as digit separators but may also match unintended strings.