I'm finally certain I'm trans. 100% certain. It has finally gotten to the point where, if I don't do something soon, I'm not sure I can be anything approaching okay for much longer. I'm sure I need to move forward. I'm sure I need to come out--and I'm sure that, even if my family takes it badly, I can be okay with it, eventually. I need to take steps to be myself, so I can be happy and productive in my life. I'm almost ready to tell my parents (though I might wait until after grad school, just in case, depending on whether I can keep it together that long). Sorry, I think this post was primarily to solidify it all in my own head. It's finally real. I can finally start planning. In some ways, that feels awesome.
Congrats. It's always a good thing to know for sure, especially after so much inner battling and doubt (speaking mostly from experience here). Let us know if we can help you out in any way through your journey.