how far do you have to be to find out what sex your having?

[Allicia]

i really want to know what im having, manly so i can start buying my babys stuff but i dont know how far you need to be to find out, i am 10 weeks now but my sister says i have to wait till in about 18 weeks whats the earliest you can find out what your having?

 

[Crazy Claire]

it usually at you 20 week scan but earlier if you have a private 3d scan