Ear training
Almost everyone can learn to hear pitch — true tone deafness is rare. Each drill starts with big, easy differences and gets finer only as you get them right.
Ear check
Twelve short listening questions, about three minutes. Take it now, and again in a month to see how far you've come.
Perfect pitch (experimental)
Naming a note with nothing to compare it to. Honestly: in the few adult studies, about 1 in 6 to 1 in 10 people reached full perfect pitch after many hours. Most improve, but not all the way. The drills above help a pianist more. Try it if you're curious.