I did the NIPT blood test at 10 weeks which checks for chromosomal abnormalities and they can also tell you the gender with the same test. Otherwise it's generally at the 20 week anatomy/anomaly scan.

Scan at 20 weeks but apparently they can tell with blood tests earlier now but I didn't get that

Apparently you can tell after 13 weeks but you usually get a scan at 12 weeks and then 20 weeks.