Use the free tool below: your data never leaves your browser — all work happens on your device, and nothing is uploaded to any server.
One note, several pitches: what concert pitch means
Ask three musicians what frequency the note A above middle C should have, and you may get three answers: 440, 432 and 415 hertz are all in regular use. Each answer is called a concert pitch, or reference pitch, because it sets the pitch of every other note an ensemble plays. The note names stay the same, but the actual sound shifts up or down. This converter shows you exactly how much, for any note you choose.
The modern standard, A440, was adopted internationally in the twentieth century, and it is what most tuners, pianos and pop recordings use today. A442 is a slightly sharper reference favoured by some orchestras, who feel it gives a brighter sound. A432 is popular with some players and listeners who prefer a slightly warmer, lower sound. A415 is the baroque reference, about one semitone below A440, and it is the standard choice for historically informed performances of Bach, Handel and their contemporaries.
How to use the converter
Choose a note and an octave, then choose a reference pitch. The tool instantly shows the frequency of your note at that reference, the frequency it would have at A440, and the difference in cents. A cent is one hundredth of a semitone, so a difference of 100 cents is exactly one semitone, and a difference of 50 cents is a quarter tone, halfway between two neighbouring notes.
The comparison table below the result lists the same note at A432, A415, A440 and A442 side by side, so you can see the whole spread at a glance. For A itself the numbers are the references by definition, but for other notes the differences are proportional: every note moves by the same number of cents, because changing the reference stretches or squeezes the whole pitch system evenly.
Press the play button to hear your note at the chosen reference. Hearing the difference is more useful than reading it, because a change of 32 cents, which is the gap between A440 and A432, is small enough that many listeners notice it only when two versions play back to back. Try playing the same note at A440 and then at A415 to feel the semitone drop.
Why ensembles must agree on one reference
If a violin tunes to A442 and a piano is tuned to A440, every note they play together will be slightly out of tune, by about 8 cents. That is small, but in a chord it creates a slow beating sound that listeners hear as roughness. In a large orchestra the effect multiplies, which is why the oboe traditionally gives the reference note before a concert: the whole group tunes to one A, and everything else follows.
Recording sessions have the same problem in a different form. A singer who records a vocal over a backing track tuned to A440 cannot simply drop in a guitar part recorded at A432; the two will clash. Studios therefore state the reference in their session notes, and sample libraries are usually recorded at A440 for the same reason. When you collaborate with other musicians, agreeing the reference first saves a painful retune later.
Baroque pitch and historical performance
A415 is not a mistake or a flat A440. In the baroque period there was no single world standard, and surviving organs and wind instruments cluster around several pitches, with A415 a convenient modern shorthand for music about a semitone below today’s standard. Playing Bach at A415 with period instruments gives a darker, gentler string sound and suits the voices better, which is why specialist ensembles adopt it.
If you sing along with a baroque recording and find the key awkward, check the reference before you blame your voice. A piece in D major at A415 sounds in about Db major at A440, so a singer may be straining a semitone higher than the composer intended. Transposing the recording down, or retuning your instrument, solves a problem that practice alone cannot.
Practical tips
Keep your tuner set to the reference your group uses, and check it before every rehearsal, because tuners remember their last setting and a leftover A432 can waste twenty minutes. If you play a fixed-pitch instrument such as a piano, changing reference means a full retune by a technician, so agree the reference before booking one. And if you are choosing between A440 and A432 for your own listening, trust your ears: the converter gives you the numbers, but the preference is personal, and no frequency is more natural than another.
Related calculators
- Spanish version
- Note Frequency Chart Generator – Every Note from C0 to C8 with Hz Values
- Transposing Instrument Converter – Written vs Concert Pitch for Bb, Eb and F