The terms are not of the same usage these days. A Fortepiano is
generally a pre-modern instrument, or copy thereof. Mostly, the so-
called "Mozart Piano" or instruments of that general era.
It is very rare to hear anyone talk of a Pianoforte any more! It seems
to be much more common to hear of our beloved Steinways referred to
as "accoustic pianos"; as opposed to the digital fakes!
Kurt von Schakel