Not really, because being transgender is a subjective experience. The only person who can actually know whether or not they’re trans is the person living with feelings of gender incongruence (the feeling that one’s true gender doesn’t align with the one they were assigned at birth).
There isn’t a psychological test, blood test, or medical scan. It isn’t something a person chooses to be, and it certainly isn’t a mental disorder.
Still, due to the realities that still exist in society, you may find yourself being asked for a diagnosis at some point.