Piano note
A0 Piano Note Frequency
A0 is key 1 of the 88 on a standard piano, with a frequency of 27.50 Hz when the piano is tuned to A4 = 440 Hz.
27.50 Hz
A0 at a glance
- Frequency (A4 = 440 Hz)
- 27.50 Hz
- At A4 = 442 Hz
- 27.63 Hz
- At A4 = 432 Hz
- 27.00 Hz
- Piano key number
- 1 / 88
- MIDI note number
- 21
- Octave
- 0
- Key colour
- White key
- Wavelength in air
- 12.47 m
- Period (one vibration)
- 36.36 ms
- Register
- Low bass
Wavelength assumes sound travels at 343 m/s (air at about 20 °C).
About this part of the keyboard
A0 is the lowest note on a standard 88-key piano.
These are the lowest keys on the piano. On most pianos each of these notes has a single heavy string wound with copper wire; the winding adds mass so the string can sound a very low pitch at a practical length. The fundamental is weak this low, so much of what you hear is the higher partials, and tuners set these notes slightly flat of the theoretical frequency (stretch tuning).
Neighbouring keys
Is your A0 in tune?
Play A0 on your piano and our free online tuner will show how many cents it is from 27.50 Hz.
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