Newton-metre (Nm)

Torque is rotational force. A robot arm or leg does not push in a straight line — it pivots around a joint, so what matters is how much twist the motor at that joint can produce. That number is given in newton-metres, written Nm.

For scale: a cordless screwdriver might manage 10 Nm. A car engine sits in the hundreds. A humanoid hip or knee joint rated around 450 Nm can swing a leg fast enough to move an adult human body, which is exactly why a fighting humanoid can knock someone over.

When you read a robot spec sheet, torque tells you what it can do physically, while payload tells you what it can carry. High torque also means high risk: the same joint that lifts a crate can crush a hand, which is why safety standards for robots working near people cap force and speed.