Piano Tuning Calculator

Calculate target frequencies and cents offsets for piano tuning with octave stretch compensation.

Key Number (1-88)

Reference A4 Frequency

Stretch Factor

Temperament

Tab to move between fields

Target Frequency

440 Hz

Cents from Equal Temp0 cents

Octave Stretch0 cents

Beat Rate0 beats/sec

Tuning Order Priority7

How to Use This Calculator

Enter Key Number (1-88), Reference A4 Frequency, and Stretch Factor.
Set Temperament.
Review the Target Frequency (Hz) result.
Use Cents from Equal Temp (cents) and Octave Stretch (cents) to inform your decision.
Use the chart to visualize the results and explore different scenarios by adjusting inputs.

How the result changes with Key Number (1-88)

Key Number (1-88): Piano key number. A4 is key 49, middle C (C4) is key 40.
Reference A4 Frequency: Concert pitch reference. Standard is 440 Hz.
Stretch Factor: Inharmonicity compensation. 0=no stretch, 1=standard, higher for older pianos.
Temperament: 1=Equal temperament, 2=Well-tempered.

Identify Input Parameters
4 parameters
Key Number (1-88) = 49, Reference A4 Frequency = 440, Stretch Factor = 1, Temperament = 1 = 4 input(s) provided
Calculate Target Frequency
440 = 440
Calculate Cents from Equal Temp
0 = 0
Calculate Octave Stretch
Octave Stretch
0 = 0

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