When do you press the octave key on saxophone?
The octave key is the small key above your left thumb. Press it, and the note jumps up an octave with the same fingering. The rule for when to use it is short: D on the fourth line and everything above it. Here's why, and how to switch smoothly.
Want to drill them? Practice these fingerings in Woodwind Trainer →
What the octave key does
The octave key opens a tiny vent near the top of the saxophone. That vent makes the air inside vibrate in two halves instead of one, and the note goes up exactly one octave. Low D becomes middle D; low G becomes high G.
Which notes use it
| Notes (written) | Octave key? |
|---|---|
| Low B♭ up to C♯ in the third space | No |
| D on the fourth line up to C♯ above the staff | Yes, same fingerings as an octave lower |
| High D and up (palm keys) | Yes, plus the palm keys |
So C♯ in the third space is the last note without the octave key, and D on the fourth line is the first note with it. Saxophone fingerings are the same for alto, tenor, and bari, so this rule works on every saxophone.
Saxophone vs clarinet
The clarinet's register key jumps a twelfth (an octave and a fifth), so its upper notes need new fingerings. The saxophone's octave key jumps exactly an octave, so the upper fingerings repeat the lower ones. That's because the saxophone's tube is cone-shaped, and the clarinet's is a cylinder. If you double on both, see the clarinet register key. The flute jumps an octave too; see the flute fingering chart.
Moving across the octave smoothly
The hardest move is C♯ to D: C♯ uses no fingers, and D uses all six plus the octave key. Everything has to move at once.
- Rock your thumb, don't lift it. Keep the left thumb touching the thumb rest and roll the tip up onto the octave key.
- Keep fingers close to the keys. Fingers that hover just above the keys can all land at the same moment.
- Keep the air steady. You don't need to blow harder for the upper octave. Let the key do the work.
- Practice slowly. Slur C♯ to D and back until no "blip" sneaks in between.
Common mistakes
- Forgetting the octave key on D and E. You'll get the low note instead, an octave below the band.
- Leaving it down on C or C♯. C♯ with the octave key sounds unstable and out of tune.
- Pressing it on low notes. The octave key on low D, C, or B♭ makes them warble or jump up.
- Lifting the thumb off the rest. Losing contact makes it hard to find the key again quickly.
Practice these fingerings
- Play low G, then high G with the octave key. Keep the same fingers and steady air.
- Repeat with low D to middle D, then low E to middle E.
- Slur C♯ to D slowly until every finger lands together.
Then quiz yourself in Woodwind Trainer. It shows the octave key on every fingering, so you can check which notes need it.