How many weeks do you have to be when you can find out if you're having a girl or boy?

I was 15 weeks

Via 3D Ultrasound

I saw baby gender regular ultrasound at 13 weeks and I'm confirming it in 3 weeks I'll be 21 weeks

@sheaxx, I haven't been able to go to the obgyn because I don't have insurance yet but when I went to the health department (where I found out that I was pregnant) they estimated me at 12 weeks, so if I am that means I can find out in 3 weeks?! HOW EXCITING

Usually the doctors waits until your 18 or 20 week appointment but you can go to a ultrasound place and pay money to find out sooner they usually start at 15 weeks

I found out at 19 weeks.

I found out at 13 weeks by 2d ultrasound I paid for it at a private us place