how do you calculate the horsepower of electric motors?

As Nacho says, its usually stated, you can get a guess from the electrical ratings, and you can, if you are absolutely forced to, do it by measurement. If you know the torque, and the speed it spins at, then Torque in Newton-metres x speed in revs/second gives power in Watts. Divide by ~750 for Hp. Steve
orksecurity6 years ago
Note too that "horsepower" originated as a marketing term and has very little to do with the amount of work an actual horse can perform.
loki17 (author)  orksecurity6 years ago
good point
NachoMahma6 years ago
. I just look at the nameplate - it's usually one of the first params listed.