About the Torque Converter
This torque converter changes a twisting force between newton-metres (N·m), foot-pounds (ft·lbf), inch-pounds (in·lbf), inch-ounces, newton-centimetres, kilonewton-metres and kilogram-force metres or centimetres. Enter a value, choose its unit and the unit your torque wrench or manual uses, and the full set of equivalents appears underneath.
Mechanics use it to set a wrench from a service manual in another system — wheel lug nuts, cylinder-head bolts, bicycle stems and carbon parts all have tight specs. It also helps compare engine torque figures quoted in N·m and lb-ft, and read small-motor or servo ratings given in in·oz or kgf·cm.
The "pound" in foot-pounds here is pound-force (4.4482 N), which is what torque specs mean. Over-tightening can strip threads or crack parts, so always use the manufacturer’s figure and a calibrated wrench rather than a rounded conversion.
How to use the torque converter
- 1Enter the torque value from your manual or spec sheet.
- 2Select the unit it is given in.
- 3Select the unit your torque wrench reads.
- 4Set the wrench to the converted value shown.
Formula and method
Torque is force multiplied by the distance from the pivot, so each unit is a force unit times a length unit. One foot-pound-force is 4.4482216 N × 0.3048 m = 1.3558179 N·m, one inch-pound-force is 4.4482216 N × 0.0254 m = 0.1129848 N·m, and there are exactly 12 in·lbf in 1 ft·lbf.
Kilogram-force units use standard gravity, 1 kgf = 9.80665 N, so 1 kgf·m = 9.80665 N·m and 1 kgf·cm = 0.0980665 N·m. The converter changes your value to N·m and then into the target unit.
- N·m
- Newton-metre (SI unit of torque)
- ft·lbf
- Foot-pound-force = 1.355818 N·m
- in·lbf
- Inch-pound-force = 0.112985 N·m
- kgf·m
- Kilogram-force metre = 9.80665 N·m
Worked examples
100 ft-lbs lug nut torque in N·m
100 × 1.3558179 = 135.58 N·m. Because a foot has 12 inches, the same torque is 1,200 in·lbf.
25 N·m bike part in inch-pounds
25 ÷ 0.1129848 = 221.27 in·lbf, or 18.44 ft·lbf. Small specs like this are usually set with an inch-pound wrench.
10 kgf·m from an older manual
10 × 9.80665 = 98.07 N·m. Dividing by 1.3558179 gives 72.33 ft·lbf.
Frequently asked questions
How do I convert N·m to ft-lbs?+
Multiply newton-metres by 0.737562 (or divide by 1.355818). For example, 200 N·m × 0.737562 = 147.5 ft·lbf.
How many inch-pounds are in a foot-pound?+
There are exactly 12 inch-pounds in one foot-pound, because a foot is 12 inches. So 30 ft·lbf = 360 in·lbf.
Is lb-ft the same as ft-lb?+
For torque, yes. Engineers often write lb·ft to distinguish torque from the foot-pound unit of energy, but the numbers are identical: 1 lb·ft = 1 ft·lb = 1.3558 N·m.
What is kgf·cm used for?+
Kilogram-force centimetres are common on small electric motors, servos and some Asian tool specs. 1 kgf·cm = 0.0980665 N·m, or about 0.868 in·lbf.
Can I round torque conversions?+
Rounding to the nearest whole unit is fine for most wheel and engine bolts, but for small fasteners and carbon parts keep one decimal — a 1 N·m error on a 5 N·m spec is 20%.