Need a custom script for text to number

I need a number text box, and I got it to default here.  but the problem is I can't put 6digit number with 'comma'. I know if I type without comma that will be correct n It's automatically shown 'comma'. if I take the box None and type number with a comma then they didn't count after comma.

so... I need a custom javascript to convert the text to the number or give me any other option to solve that.
[sorry for my bad english]