Regex for number check below a value

Question

I\'m still a beginner at regex so this is a little above me currently.

I need to validate a number input to two characters and it can\'t be more than the value 12.

Answer 1

0[0-9]|1[0-2]

Description:

 [0-9] : number between 00 and 09
     | : or
1[0-2] : and if starting with 1, next number should be between 0 -1 (testing 10-12)