This question already has an answer here:
I am new to sax, but was a B♭ clarinet player in high-school band (years ago); now I play some guitar and piano. I just got an inexpensive soprano sax (Mendini). Since it is a B♭ instrument, help me remember how to tune it using my piano. When I play a C on the saxophone, the tuner shows a B♭. Is that how it is supposed to be, and if so how should I go about transposing? Obviously I can't play from a piano lead sheet if that's the case.