Question

I’m a newbie to regex and trying to create a regex to validate pass phrases. I would like to validate that the pass phrase has:

• n number of words or more
• words should be separated by spaces
• words, each with n characters or more
• a number in at least one of the words
• at least one special character in one of the words

This is what what I have so far

^(?=.*?((?:.*?\b[a-zA-Z0-9]{2,40}\b)\s*){3,})(?=.*?[@#$%^&+=])(?=.*?[0-9]).*$

It matches this Pe2sI#sHy?ThYulU# phrase that does not have at least 3 words (no spaces). What am I doing wrong?

Answer 1

You should use \s+ instead of \s*. The latter allows zero spaces, the former requires at least one. But your regex is overly complicated. Try this:

^                 # Start of string
(?=.*\d)          # Assert at least one digit
(?=.*[@#$%^&+=])  # Assert at least one special char
\s*               # Optional leading whitespace
(?:               # Match...
 \S{2,}           #  at least 2 non-spaces
 \s+              #  at least 1 whitespace
){2,}             # at least 2 times
\S{2,}            # Match at least 2 non-spaces (making 3 "words" minimum)