What's the difference between force and weight?

Force in newtons is mass times acceleration (F=ma). Kilograms-force is a unit some torque wrenches and older gauges use to describe the force exerted by a 1 kg mass under standard gravity - it's a force unit, not a mass unit, even though it's named after one.

Why do US torque specs use lb-ft or lb-in?

Pound-feet (larger fasteners, like lug nuts) and pound-inches (smaller fasteners, like electronics screws) are the customary US units for torque, while newton-metres are standard almost everywhere else and in most engineering specs.

Is 1 lb-ft the same as 12 lb-in?

Yes - lb-ft and lb-in differ only by the length unit (feet vs inches), so 1 lb-ft = 12 lb-in exactly, unlike the newton-based conversions which involve a non-round factor.

Force & Torque Converter — N, lbf, kgf, Nm, lb-ft

Convert force between newtons, pounds-force, kilograms-force, and dynes — or torque between newton-metres, pound-feet, and pound-inches.

How this works: Enter a value in either the Force or Torque panel and every other unit updates instantly using fixed conversion factors (1 lbf = 4.44822 N, 1 kgf = 9.80665 N, 1 lb·ft = 1.35582 N·m).

Enter a force value

Enter a torque value

Standard gravity (9.80665 m/s²) used for force/weight equivalents. Torque wrench and fastener specs should always be checked against the manufacturer's own figures. See Terms.

How this works

Enter a value in either the Force or Torque panel, and every other unit in that panel updates instantly using fixed, internationally defined conversion factors — 1 lbf (pound-force) = 4.44822 newtons, 1 kgf (kilogram-force) = 9.80665 newtons, and 1 lb·ft (pound-foot) = 1.35582 newton-metres.

Force and torque are related but different physical quantities — force is a straight-line push or pull, while torque is a rotational force applied at a distance from a pivot point — so the two panels convert independently rather than being interchangeable with each other.

This is particularly useful for anything involving specifications from different regions or standards, since torque wrenches, engine specifications, and mechanical fasteners are commonly rated in different unit systems depending on where they're manufactured or which standard they follow.

FAQ

What's the difference between force and torque?

Force is a straight-line push or pull, measured in units like newtons or pounds-force. Torque is a rotational force applied at a distance from a pivot point, measured in units like newton-metres or pound-feet — related concepts, but not interchangeable.

Why do I need to convert between different force or torque units?

Specifications, tools, and manuals from different countries or manufacturers often use different unit systems — a torque wrench spec sheet from one region might use newton-metres while another uses pound-feet, so converting lets you compare or apply specs correctly regardless of source.

How precise are the conversion factors used?

They use exact, internationally defined constants — for example, 1 lbf is defined as exactly 4.44822 newtons — so conversions are as accurate as the underlying standard definitions.

Can I convert directly from a force unit to a torque unit?

No — force and torque are different physical quantities, so there's no direct conversion between them without knowing the distance from the pivot point (lever arm) involved, which is why they're kept as separate panels.

Force & Torque Converter

How this works

FAQ

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