Regular expressions for passwords
This is a link post for some of the regular expressions that can be used for passwords. Specifically, you can use them for asp.net's passwordStrengthRegularExpression. Note: Be sure to test them *before* you use them in a production app. The table indicates the minimum length, if it requires at least one upper, lower, digit or special character. Expression Len Upper Lower Digit Special ^.*(?=.{10,})(?=.*\d)(?=.*[a-z])(?=.*[A-Z])(?=.*[@#$%^&+=]).*$ 10 Y Y Y Y ^.*(?=.{8,})(?=.*\d)(?=.*[a-z])(?=.*[A-Z]).*$ 8 Y Y Y N ^.*(?=.{10,})(?=.*\d)(?=.*[a-z])(?=.*[A-Z])(?=.*[@#$%^&+=]).*$ 10 Y Y Y Y