Regular expression for matching HH:MM time format

Question

I want a regexp for matching time in HH:MM format. Here\'s what I have, and it works:

^[0-2][0-3]:[0-5][0-9]$

This matches everything from

Answer 1

You can try the following

^\d{1,2}([:.]?\d{1,2})?([ ]?[a|p]m)?$

It can detect the following patterns :

2300 
23:00 
4 am 
4am 
4pm 
4 pm
04:30pm 
04:30 pm 
4:30pm 
4:30 pm
04.30pm
04.30 pm
4.30pm
4.30 pm
23:59 
0000 
00:00