How this calculator works
The newton-metre is the SI unit of torque: one newton applied at a lever arm of one metre. Every other unit is converted through it using exact definitions. One pound-force is 4.4482216152605 N and one foot is 0.3048 m, so one foot-pound is 1.3558179483314004 N-m. Kilogram-force units use standard gravity of 9.80665 m/s2, and one dyne-centimetre is 10 nanonewton-metres.
Formula
N-m = lbf-ft x 1.3558179483314004. N-m = lbf-in x 0.1129848290276167. N-m = kgf-m x 9.80665. N-m = kgf-cm x 0.0980665. N-m = N-cm / 100 = N-mm / 1000 = kN-m x 1000. N-m = dyn-cm x 0.0000001.
Worked example
1 N-m is 0.737562 lbf-ft, 8.85075 lbf-in, 0.101972 kgf-m and 10,000,000 dyn-cm. 100 lbf-ft is 135.582 N-m. 1 kN-m is 1,000 N-m.
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Frequently asked questions
Is a newton-metre a joule?
They have the same dimensions but different meanings. A joule is energy, the dot product of force and displacement. A newton-metre is torque, the cross product of force and lever arm. Keeping separate names prevents confusion.
What does a torque wrench marked 100 N-m mean?
It means 100 newtons applied at one metre from the pivot, or any combination with the same product, such as 50 N at two metres. The wrench clicks when the fastener reaches that torque.
Why are kilogram-force units still used?
Older service manuals and some equipment made before SI adoption list torque in kgf-m or kgf-cm. Converting to N-m keeps the specification usable with modern tools.