Why is this regex allowing a caret?

Question

http://regexr.com/3ars8

^(?=.*[0-9])(?=.*[A-z])[0-9A-z-]{17}$

Should match \"17 alphanumeric chars, hyphens allowed too, must include at le

Answer 1

You're allowing A-z (capital 'A' through lower 'z'). You don't say what regex package you're using, but it's not necessarily clear that A-Z and a-z are contiguous; there could be other characters in between. Try this instead:

^(?=.*[0-9])(?=.*[A-Za-z])[0-9A-Za-z-]{17}$

It seems to meet your criteria for me in regexpal.