Validate password with regular expression on php

Question

I am not clear with regular expression of php. I would like to validate password with below rules:

Password contain at least 8 characters
Password contain at least 1 letter
Password contain at least 1 digit

Could anyone help me?

You could write out those conditions explicitly without using a regular expression. — icktoofay, May 21 '14 at 08:21

score 2 · Answer 1 · edited May 23 '17 at 10:32

public function checkPassword($pwd, &$errors) {
$errors_init = $errors;

   if (strlen($pwd) < 8) {
      $errors[] = "Password too short!";
   }

   if (!preg_match("#[0-9]+#", $pwd)) {
      $errors[] = "Password must include at least one number!";
   }

   if (!preg_match("#[a-zA-Z]+#", $pwd)) {
      $errors[] = "Password must include at least one letter!";
   }     

   return ($errors == $errors_init);
}

source: https://stackoverflow.com/a/10753064/1676962

score 2 · Answer 2 · answered May 21 '14 at 08:27

2

You could use this regex :

preg_match('/(^(?=.*\d)(?=.*[a-z]).{8,}$)/i', $password);

Details :

(?=.*\d) : at least one digit
(?=.*[a-z]) : at least one letter
.{8,} : 8 or more characters
/i : case insensitive regex

Regular expression visualization

answered May 21 '14 at 08:27

zessx

68,042
28
135
158

score 0 · Answer 3 · answered May 21 '14 at 08:33

0

this is the regex :

^((?=.*\w)|(?=.*\d])).{8,}$

demo here : http://regex101.com/r/iU4mH1

answered May 21 '14 at 08:33

aelor

10,892
3
32
48

This will match `11111111`, but there's not a single letter. (same for `aaaaaaaa`) – zessx May 21 '14 at 08:48
You misunderstand `\w` – OGHaza May 21 '14 at 09:41

Validate password with regular expression on php

3 Answers3