The number of notes a flute can play depends on the person playing it. However, a top-notch, professional player can easily play thirty-eight or more notes. This can span over three octaves, and will use certain keys available only on intermediate or professional-grade flutes.
The great thing about flutes is the fact that their flat key is easily accessible, giving the availability of more notes to players who may not be as skilled.
Most flutes have sixteen key openings to cover an equal tempered octave. Many modern flutes can reach a range of three octaves with anywhere from sixteen to twenty openings to play. The highest note depends upon how strong you are at playing it. The concert flute is capable of performing a wide range of pitches.
The foot extension allows the flute player to reach B immediately below middle C. Some performers can reach F. There are, altogether, about twenty-one notes. These include a,b,c,d,e,f and g notes in conjunction with all of their sharps and flats. The flute notes depend on the foot joint.