QuickUnits

Torque

Kilogram-force centimetres to newton-metres

1 kgf·cm = 0.0980665 N·m

—

One kilogram-force centimetre is 0.0980665 newton-metres. It is the small-torque unit of the metric gravitational system, and it turns up constantly in specifications for hobby servos and small motors.

About the units

A kgf·cm is one kilogram-force acting one centimetre from the axis. It combines the deprecated kilogram-force with the centimetre, and it survives mainly because a whole industry standardised on it: radio-control servos, small geared motors and hobby actuators are almost universally specified in kilogram-force centimetres, regardless of where they are made. A servo advertised at 10 kg·cm — with the force part usually left out of the label — produces 0.98 N·m, which is enough to lift a kilogram on a one-centimetre arm or a hundred grams on a ten-centimetre one.

The exact factor

The exact value is 0.0980665 N·m per kgf·cm, since a kilogram-force is 9.80665 N and a centimetre is 0.01 m. The approximation of 0.1 is high by two per cent and entirely adequate for hobby work: a 20 kg·cm servo is about 2 N·m. Going the other way, 1 N·m is 10.197 kgf·cm. The relationship to pound-inches, the other small-torque unit in common use, is 1 kgf·cm = 0.868 lbf·in.

Where you meet this conversion

Radio-control models, robotics and hobby engineering, where servo torque is the headline specification and is always in kilogram-force centimetres. Small geared DC motors from Asian manufacturers use the same unit. Understanding the arm-length relationship matters more than the conversion itself: a servo rated 15 kg·cm delivers 15 kilograms of force at one centimetre, but only 1.5 at ten centimetres, and that is what determines whether it can move a given linkage.

Common values

Value (kgf·cm) Converted (N·m)
1 0.0980665
2 0.196133
5 0.490333
10 0.980665
25 2.45166
50 4.90332
100 9.80665
500 49.0333
1 000 98.0665

Values are rounded for reading. The converter above keeps full precision.

The other way around

1 N·m = 10.1972 kgf·cm

Newton-metres to kilogram-force centimetres multiplies by 10.197. For hobby work, multiplying by ten is close enough — a 3 N·m motor is about 30 kg·cm, against the true 30.6.

Value (N·m) Converted (kgf·cm)
1 10.1972
2 20.3943
5 50.9858
10 101.972
25 254.929
50 509.858
100 1 019.72
500 5 098.58
1 000 10 197.2

Related conversions

All torque conversions