Torque Converter
Convert newton-metres, pound-feet, pound-inches and kilogram-force metres.
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Understanding rotational force
Torque describes a rotational or twisting force — the kind of force applied when you tighten a bolt, turn a steering wheel, or an engine crankshaft delivers power to a car's wheels. Unlike linear force, torque is always described relative to a distance from a pivot point, which is why torque units combine a force unit with a length unit: newton-metres, pound-feet, and pound-inches. This tool converts between the metric and imperial torque units you'll encounter across mechanical, automotive, and DIY contexts.
Why torque specifications matter so much
Getting a torque specification wrong when assembling machinery, tightening wheel lug nuts, or working on an engine isn't just a theoretical concern — under-tightening a fastener can allow it to loosen under vibration, while over-tightening can strip threads or crack a component. Manufacturer torque specifications are often given as a precise figure with a tolerance range, and correctly converting between the unit your torque wrench displays and the unit your service manual specifies is a genuinely practical safety step, not just a unit-conversion curiosity.
Newton-metres versus pound-feet versus pound-inches
The newton-metre (N·m) is the standard SI torque unit, common in most of the world's automotive and engineering documentation. Pound-feet (lbf·ft) is the standard in US automotive contexts for larger torque values, like engine or wheel specifications, while pound-inches (lbf·in) is used for smaller torque values, like electronics assembly or small fastener specifications, where pound-feet would produce awkwardly small decimal numbers. Because pound-feet and pound-inches differ by a factor of 12 (the same 12-inches-in-a-foot relationship as length), mixing them up is a surprisingly common and consequential error — always double-check which one a specification is actually using before setting a torque wrench.
Where this tool helps
DIY mechanics and cyclists working from a service manual that specifies torque in a different unit than their torque wrench displays, engineers converting design specifications between metric and imperial torque units for international manufacturing, and hobbyists assembling furniture, electronics, or machinery that includes torque specifications from an overseas manufacturer all rely on quick, accurate torque conversion.
A safety-focused final note
When a torque specification genuinely matters for safety — wheel lug nuts, engine components, structural fasteners — always double-check the converted figure against a second source or the original manufacturer documentation, and use a properly calibrated torque wrench rather than estimating by feel. This converter is a reliable tool for translating between units, but it can't substitute for a calibrated instrument and the correct original specification.
A quick worked example
If a manual specifies wheel lug nuts at 100 N·m and your torque wrench only displays lbf·ft, entering 100 with newton-metre selected as the 'from' unit and pound-foot as the 'to' unit instantly shows the equivalent — approximately 73.8 lbf·ft — so you can set your wrench correctly without doing the arithmetic by hand or risking a transcription error under time pressure.
Checking your torque wrench's unit setting
Many modern torque wrenches let you switch their display between N·m and lbf·ft with a small button or dial — before starting a job, it's worth confirming which unit the wrench is currently set to display, since misreading the active unit is just as likely a source of error as a manual conversion mistake, and this converter is a fast way to sanity-check that the number on the wrench actually matches what the specification calls for.
Frequently asked questions
How many pound-feet are in a newton-metre?
One newton-metre equals approximately 0.738 pound-feet. Conversely, one pound-foot equals approximately 1.356 newton-metres.
What's the difference between pound-feet and pound-inches?
Pound-inches are smaller — there are 12 pound-inches in every pound-foot, matching the 12-inches-per-foot relationship in length units. Pound-feet is typically used for larger torque values, and pound-inches for smaller ones.
Why does torque have a distance unit in it?
Torque describes a rotational force applied at a distance from a pivot point — the same force applied further from the pivot produces more torque, which is why torque is always expressed as force multiplied by distance, like newton-metres or pound-feet.
How important is it to get torque conversion right for car maintenance?
Very important. Under- or over-tightening fasteners like wheel lug nuts or engine components due to a unit conversion error can lead to component failure or safety issues. Always double-check a converted torque figure against the original manufacturer specification.
What is kilogram-force metre used for?
Kilogram-force metre (kgf·m) is an older metric torque unit, still occasionally seen in some manuals and specifications, particularly from certain Asian and European manufacturers, alongside or instead of the SI-standard newton-metre.