I found out at 15 weeks at one of those 4D ultrasound places. You just gotta be careful cause that is very early. I went in there telling myself that if they says it's a boy then it's a boy but if they say it's a girl it's possible it could be a boy. I was told at 15 weeks I was having a boy and then just yesterday at my 21 week ultrasound they verified that he is a boy.