How tall will he mature??

[Ace99]

I just recently bought a colt that is around 5-7 months (the owners weren't even positive). He is very sweet, but I'm needing to know how big he will mature too before I get attached and he turns out to be too small. I'm not sure what the height of his dam and sire was, or even what they looked like! If I measured correctly he is around 9 hands tall. The thing is he has long, springy looking legs.. I don't understand really. I had someone who knew about horses to look at him and he said he wasn't going to get a whole lot bigger. Please help!
So if he's 9 hands at 5-7 months, how much taller will he mature to?

 

[throughtheforest]

Well there's not much to go by to estimate height at maturity, have you got any idea of what breed/s sire and dam are?

 

[Ace99]

Not really, but he's a Paint. Not that that's a breed inpaticular, but I heard they're small? Though I know they can be painted and a pony..
Do you know the usual height of horse foals around this age?
Thanks

 

[Meowy Catkin]

http://www.ultimatehorsesite.com/info/stringtesting.html

String test him.