Tuner

Hz
−50 −40 −30 −20 −10 0 +10 +20 +30 +40 +50

Hz

cents

Microphone off

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Note names

Tunings

Open-string frequencies in hertz with A4 at 440 Hz, in twelve-tone equal temperament. Each row runs from the highest-numbered string down to string 1.

TuningStrings

Reading the tuner

The needle and the cents figure show how far the note is from the target. A cent is one hundredth of an equal-tempered semitone, so an octave spans 1200 cents. Within 3 cents of the target the display turns green.

The strobe band drifts left when the note is flat and right when it is sharp. The further off the note, the faster it moves; on pitch it stands still.

With an instrument selected, each note is compared with the nearest string. Selecting a string plays its reference tone and holds the comparison to that string until you choose Auto.

Frequencies follow twelve-tone equal temperament: a note n semitones above A4 (n is negative below it) sounds at A4 × 2n/12. With A4 at 440 Hz, the standard tuning frequency in ISO 16, the A two octaves below sounds at 110 Hz. The tuner reads notes from A0 to C7.

Keyboard

Space
Start or stop the microphone
1 to 6
Play that string and tune to it
A
Match the nearest string
+ −
A4 up or down by 1 Hz
Esc
Stop the reference tone