Piano Keys: 88 Keys, Note Names and Touch
Piano keys are where every piece of music begins. A standard keyboard has 88 keys, 36 black and 52 white, spanning just over seven octaves, from the lowest A on the left to the highest C on the far right. Once you understand how the keyboard is laid out, it stops being a long row of black and white stripes and becomes a clear map your eye learns to read in no time.
A map that repeats itself
The keyboard is built from a single pattern of 12 keys, seven white and five black, repeated again and again from left to right. Each repetition is an octave, and within every octave the notes rise in semitones, so each key is a semitone higher than the one to its left. The black keys sit between the white ones, first in a pair and then in a group of three, and that is what guides the eye: the white key just to the left of the pair of black keys is always C.
The white keys play the seven natural notes, known as do, re, mi, fa, sol, la and ti, or C to B in English. The black keys give the sharps and flats in between, and if you play only the black keys you get a five-note scale, the pentatonic scale.
Middle C and A440
Middle C, marked C4, sits near the center of the keyboard and is the 40th key from the left. In written music it is the note right between the treble staff and the bass staff, which makes it the most familiar reference point on the keyboard. Nine keys to its right is A, the 49th key, whose frequency is set at 440 Hz and serves as the reference for the whole keyboard.
From there the range stretches in both directions: the lowest A vibrates at about 27.5 Hz and the highest C at about 4,186 Hz. Alongside the standard keyboard there are also extended models, such as the Bösendorfer Imperial with 97 keys, and we told the story of how the keyboard grew from five octaves to seven and a quarter in our guide to the history of the piano.
What a key is made of
Under its surface, every key is a long wooden lever, most of it hidden inside the piano. Today it is usually made of spruce or basswood, and quality pianos mostly use spruce. Its back end sets off the action that drives the hammer, a chain we explain step by step in How a Piano Works.
Key surfaces today are covered with materials developed especially for the fingers. On some of its digital pianos, Yamaha covers the white keys with a synthetic material that absorbs moisture from the fingers and keeps a steady grip even after hours of playing, while Kawai uses a cellulose-fiber surface that absorbs the natural oils of the hands and keeps its look for decades.
How much a key weighs, acoustic and digital
The feel of a keyboard is measured in grams. The journal of the Piano Technicians Guild (PTG) gives a range of 45 to 55 grams as the weight that, placed at the front of a key, brings it down slowly. On most pianos the bass keys are slightly heavier than the treble keys, and the bass hammers are larger too.
In fast, strong playing the weight of the hammer itself comes into play, so two pianos with the same number of grams can feel very different under your hands. That is exactly why the best way to get to know a touch is to play it.
Advanced digital pianos have 88 weighted keys, just like an acoustic piano. On Yamaha's Graded Hammer keyboards, for example, the touch weight changes along the keyboard, heavier in the low notes and lighter in the high ones. Electronic keyboards also come with 61 or 76 keys, while 88 keys open up the entire piano repertoire. More on choosing one in our Digital Piano guide.
Come and feel it yourself
At our store and gallery at 28 Ben Atar, you can sit down at upright and grand pianos, find middle C, and compare the touch of several pianos side by side. We'd be happy to show you what happens under the keys while you play. We're here for you.
Links: How a Piano Works · The History of the Piano · Piano Pedals · Digital Piano · How to Choose an Upright Piano · How to Choose a Grand Piano
Frequently asked questions
How many keys does a piano have?
Most pianos have 88 keys, 36 of them black, running from the lowest A to the highest C. Older pianos sometimes have 85 keys, and a few special models, such as the Bösendorfer Imperial, have 97.
How do I find C on the keyboard?
Look for a pair of black keys. The white key just to the left of the pair is C, and this pattern repeats in every octave along the keyboard.
Where is middle C?
Middle C, C4, is the 40th key from the left, near the center of the keyboard. In written music it sits between the treble staff and the bass staff.
How much does a piano key weigh?
The journal of the Piano Technicians Guild (PTG) gives a range of 45 to 55 grams as the weight that brings a key down slowly. Bass keys are slightly heavier and treble keys lighter.