Question: How many keys are on a baby grand piano? Answer : Most pianos have 88 keys, and 52 of these are white, while 36 are black. A few pianos are made with only 85 keys, and one special type of concert piano has 97 keys. A baby grand piano is called that because of the overall size of the instrument. A concert grand is the largest piano and measures nearly nine feet long or more, while a baby grand is usually five feet and eight inches long. Want to learn what each of those keys sounds like and how to play them? Check out the Piano Nanny site for lessons!