Regular Expression For Password Field

Question

I need a regular expression for a password field that:

• Must have 1 number

• Must have 1 letter (uppercase)

• Must have 1 letter (low

Answer 1

You can change the base at the end:

((?=.*\d)(?=.*[a-z])(?=.*[A-Z])[^\W_]{8,})

This solution expects your regex engine to be anchored. If not, anchor them with ^$.

[^\W_] is negated character class. It asserts that this character is not a word character or _.

As word characters covers alphanumeric characters and underscores, this double-negated character class shorthand [^\W_] is well-used for these scenarios.

You can use [[:alnum:]] as well, if your regex engine supports ascii classes.

Here is a regex demo!

Answer 2

Use [a-zA-Z0-9] instead of . and anchor your regex:

^((?=.*\d)(?=.*[a-z])(?=.*[A-Z])[a-zA-Z0-9]{8,})$