Regex for Minimum 1 character and 1 number, prevent 4 consecutive numbers and characters and having minimum length 8

Question

I want to create regex for

Minimum 1 character and 1 number in password
Prevent the “4 consecutive characters “ must be in place as well. Eg: 1234, abcd
The minimum 8 characters and the maximum is 20

I have tried:

^(?!.*(.)\1\1)(?=.*\d)(?=.*[a-z])(?=.*[A-Z])[0-9a-zA-Z]{8,20}$

^(?!.*?(?:0(?:12|98)|123|234|3(?:45|21)|4(?:56|32)|5(?:67|43)|6(?:78|54)|7(?:89|65)|876|987))(?!.*?(.)\\1{2})[0-9]{8}$

^(?=.*[A-Za-z])(?=.*\d)[A-Za-z\d]{8,20}$

^(?=.*[0-9])(?=.*[a-zA-Z])(?=\S+$).{8,20}$

But not able to get result in one regex. Please help me if any one have idea for that. Thanks in advance!

@J.Doe because I'm integrating above in iOS. If this one is not possible then any alternative way to do so in iOS Swift. — Sachin Dobariya, Jan 11 '19 at 14:34
You might find [Reference - Password Validation](https://stackoverflow.com/q/48345922/3600709) useful. — ctwheels, Mar 27 '19 at 15:26

score 0 · Answer 1 · answered Jan 11 '19 at 13:34

I don't think a regex is the right tool for the job here.

A regex engine doesn't have any concept of the natural ordering of alphanumeric characters so it's not really possible to do it in a concise way.

You could check and exclude results containing:

But you definitely should not.

so, any alternative to do this job? – Sachin Dobariya Jan 11 '19 at 13:36 — Sachin Dobariya, Jan 11 '19 at 13:36

Regex for Minimum 1 character and 1 number, prevent 4 consecutive numbers and characters and having minimum length 8

1 Answers1