Password

# Has an upper case character
.*[A-Z]
 
# Has a lower case character
.*[a-z]
 
# Has a number
.*\d
 
# Has a special character
.*[!@#$%^&*(),.?":{}|<>]

example # has a lower case character
Example # has an upper case character and a lower case character
Example1 # has an upper case character, a lower case character and a number
Example1! # has an upper case character, a lower case character, a number and a special character