I'm looking for a regex to validate if numbers are below 20 000. I can't find the right solution, I have so far this:
(^([1-9]([0-9]{0,3})|20000)$)
Which works quite ok but as soon as it gets to 10 000 it gives no matches. So I have a gap from 9 999 - 20 000.
What am I doing wrong? I don't use regex for these situations, but the 3th party program required regex for such..
Thanks!
Your regex - ^([1-9]([0-9]{0,3})|20000)$ - matches numbers from 1 till 9999 and 20000.
You may use
^([1-9]\d{0,3}|1\d{4}|20000)$
See demo
Breakdown:
^ - match start of string([1-9]\d{0,3}|1\d{4}|20000) - match one of the alternatives:
[1-9]\d{0,3} - 1 to 9 followed with 0 to 3 any digits (from 1 till 9999)1\d{4} - 1 followed with any 4 digits (to match 10000 - 19999)20000 - literally 20000$ - match the end of string