How much does a grand piano weigh?

A grand piano can weigh anywhere from 500 pounds for an apartment-size piano to 1,300 pounds for a full-sized piano used in concert halls. Most of the weight is from a large cast-iron frame, or "harp", that keeps the strings under tension.

A piano is so heavy because the frame has to support, in the case of a concert grand piano, up to 20 tons of total tension from the stretched piano strings. In addition, it has to be heavy enough to absorb the vibrations of the strings so that they are not passed along to the wooden case, making an unpleasant sound.