Regex to allow only number between 1 to 12

Question

Regex to allow only number between 1 to 12

I am trying (12)|[1-9]\d? but its not working, please help as i am new to regular expression

Answer 1

Something like

^([1-9]|1[012])$

• ^ Anchors the regex at start of the string

• [1-9] Matches 1 to 9

• | Alternation, matches the previous match or the following match.

• 1[012] Matches 10, 11, or 12
• $ Anchors the regex at the end of the string.

Regex Demo

Answer 2

Here's some readymade regex expressions for a bunch of different numbers within a certain range:

Range	Label	Regex
1 to 12	hour / month	1[0-2]|[1-9]
1 to 24	hour	2[0-4]|1[0-9]|[1-9]
1 to 31	day of month	3[01]|[12][0-9]|[1-9]
1 to 53	week of year	5[0-3]|[1-4][0-9]|[1-9]
0 to 59	min / sec	[1-5]?[0-9]
0 to 100	percentage	100|[1-9]?[0-9]
0 to 127	signed byte	12[0-7]|1[01][0-9]|[1-9]?[0-9]
32 to 126	ASCII codes	12[0-6]|1[01][0-9]|[4-9][0-9]|3[2-9]