How Many Keys Does a Piano Have? (Upright, Grand, Digital)

The piano has been around for hundreds of years, and most of us have been in the presence of one at some point or other in our lives.

So you’d think the answer to a question like ‘how many keys does a piano have?’ should be common knowledge.

Well, it turns out it isn’t!

Part of the reason could be that the number of keys varies depending on the type of piano you’re talking about. Is it a grand piano, an upright piano, a digital piano, a toy piano, a midi controller?

In this article, we’ll walk you through the differences and try and help you arrive at a definitive answer.

Standard Full Size Pianos (Upright, Grand)

example of an upright piano

So, how many keys on a piano? Well, a standard, full-sized acoustic piano (grand or upright type) has 88 keys. There are seven octaves and a minor third spanning from A₀ to C₈. The musical notes are: C-D-E-F-G-A-B or DO-RE-MI-FA-SOL-LA-SI.

The 88 key, full sized piano has 52 white keys and 36 black keys. Like other keyboard instruments, piano keys are arranged into white and black keys. With 88, it can be a job to remember where every note is, but there are some great ways to memorize piano notes.

The seven white keys are all natural notes (C-D-E-F-G-A-B). The five black keys are tuned to what are known as ‘accidental’ notes (C#/Db, D#/Eb, F#/Gb, G#/Ab, and A#/Bb). These black keys are known as flats and sharps (half-step intervals).

This graphic should help explain things:

88 Keys of a Standard Full Size Piano

Electronic or Digital Pianos

example of a digital piano

The electronic or digital piano doesn’t use metal strings and the hammer and damper system to create sound. They simply recreate the timbre of the piano electronically (when you hit a key, it plays back a recording of a full size piano).

These instruments are basically computers, and as such, are much less expensive because the cost of producing them is so much lower. The number of keys can range wildly too, from as few as 24 keys up to the standard 88 keys.

Of course, digital pianos have computer connectivity. Most will have midi compatibility and are what you’d use in conjunction with a digital audio workplace (or DAW).

As you can see in the pic below, midi controllers can have just a few keys, but some have the full 88 keys:

example of a midi controller

Electric Pianos

Back in the day, you used to find ‘electric pianos’ which were a sort of hybrid of the acoustic and the digital. They had the same mechanism found in acoustic pianos but used a built-in pickup, amp, and speaker to project the sound (rather than a soundboard). 

They’ve been mostly replaced by their digital counterparts, but you still see them from time to time. As for size, the 88 key format was most popular, but Yahama was known for making 73  and 76 key models.

Here’s an example of one:

example of an electric piano

Pianos with Extra Keys

Piano manufacturer Imperial Bösendorfer make some models with 97 keys (57 white keys, 40 black keys). with nine extra bass keys. It covering eight octaves.

Stuart & Sons make a model with a whopping 108 key grand piano (63 white keys, 45 black keys). This enormous range goes from C₀ to B₈, covering a massive nine octaves.

But that’s not the longest. Back in the nineteenth century, the Emánuel Moór Pianoforte had a gigantic 164 keys! The keys were spread out over two rows (the lower row has 88 keys, the upper row has 76). There’s only a handful in existence today.

Here’s an example of the Stuart and Sons 108 key model:

Why do Pianos Have 88 Keys? – A Short History

How did we arrive at 88 keys? Let’s take a look.

The first piano was invented around the year 1700 by Italian instrument technician Bartolomeo Cristofori. The ‘pianoforte’, as it was originally called, was an evolution of the harpsichord, but used an innovative hammer mechanism that we’re familiar with today.

Due to the immense amount of tension generated by the strings, 49 keys was the limit that piano makers could go to at the time.

Fortunately for them and for us, through the help of piano manufacturers Broadwood and Stein, they arrived at 72 keys which afforded the musician almost six full octaves.

Then finally the 88 key variant we’re familiar with today was introduced.  But why stop at 88? Why not go for hundreds of keys? Well, the notes over these 88 keys tend to be superfluous. They are either too high or too low for the human ear, so musicians and composers don’t need them.

Of course, there are exceptions such as the super grand piano made by Stuart and Sons, but that’s more for novelty than anything else. We’ve stuck to 88 keys for centuries now, I can’t see it going up.

Summary

There are plenty of exceptions that break the rule, but if you needed a definitive number I think it’s safe to say that the piano has 88 keys.

Good luck!

Photo of author
By Ged Richardson

More from this author