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regexpasswordspolicy

Regex issue with setting up a password policy

I would like to set up a password policy using Regex. Please help me, if you can. Basically, I would like to be able to have the following password rules being checked against:

  • Password should have at least 12 characters
  • It should have at least 3 lowercase characters
  • It should have at least 3 uppercase characters
  • a number
  • a special character

Thank you so much!

Best wishes,

Marcin

Solution

  • Although question must be reviewed, positive lookahead are zero width assertion and so can be useful to combine AND conditions. x flag used to increase readability.

    ^
(?=.{12,})                  # at least 12 characters
(?=(?:[^a-z]*[a-z]){3,})    # at least 3 lowercase characters
(?=(?:[^A-Z]*[A-Z]){3,})    # at least 3 uppercase characters
(?=(?:[^0-9]*[0-9]){1,})    # a number
(?=(?:[^ -\/:-@[-`{-~]*[ -\/:-@[-`{-~]){1,}) # a special character
.*$                         # to get the match

    check on regex101