Boy/Girl?

usually at the 20 week ultrasound and by than you can tell for sure unless the baby is in a bad position. You can find out with acurate results after 16 weeks.

I've heard as early as 15 weeks.

 I found all mine out at around 19 weeks. if you do a blood test you can find out at 10+weeks

Generally around 20 weeks. Sometimes with boys you can tell earlier.

I found out as early as 16 weeks with my kids

I found out 2 weeks ago at my 20 week appointment that I'm having a boy :)

Your doctor told you 24 weeks? You can find out at 20 weeks. Some women find out before that, but they tell you the sex when they do the anatomy ultrasound.

I was almost twenty weeks and it was no doubt a girl. Same with my son. 20 weeks and no doubt he was a boy.

20 weeks and in some cases, it can still be wrong.  If the boy parts do not develop til later... the reading can be inaccurate.  I know somebody that that happened to, they were ready for their little girl, but a boy came out instead. 

i was 20 weeks