Force Converter
Convert newtons, kilonewtons, pound-force and kilogram-force.
Popular Force conversions
All Force units
About Force
Force covers six units used in engineering, physics and mechanical work: newtons and kilonewtons, the SI units and the ones structural and mechanical engineering runs on; pound-force and ounce-force, the US customary units that appear on imported specs, fasteners and testing equipment; kilogram-force, a traditional unit still found on older machinery and in some European documentation; and dynes, a very small unit from the older CGS system that survives in some physics and materials contexts. People land here reading a torque or load rating from another market, working through a mechanics problem, specifying a spring or an actuator, or checking a test result. The pages used most are newtons to pound-force, pound-force to newtons, kilonewtons to newtons and kilogram-force to newtons.
The distinction worth being clear about is force versus mass, because two of the units here are named after mass units and that causes real confusion. A kilogram is a mass; a kilogram-force is the force that gravity exerts on one kilogram at the Earth's surface. Likewise a pound is used for mass in everyday speech, while pound-force is specifically a force. They are not interchangeable, and the fact that they share a name is a historical accident rather than a convenience. The practical rule is that if you are describing how much stuff there is, you want the weight and mass converter. If you are describing a push, a pull, a load or a thrust, you want this hub. Kilogram-force in particular is a legacy unit: it is still printed on older machine plates and in some documentation, but modern engineering has moved to newtons, so converting it is often the first step in reading an old spec. At the opposite end, the dyne is tiny and appears mainly in surface tension figures and older physics texts.
Each pair page shows the formula it used, walks through a worked example, and includes a reference table of common values. Everything is free, needs no sign-up, and runs entirely in your browser, so no figure you enter is uploaded. If your figure is a load spread over an area rather than a point force, the pressure converter is what you want.
Frequently asked questions
What is the difference between a kilogram and a kilogram-force?
A kilogram measures mass, the amount of matter in something. A kilogram-force measures force, specifically the pull gravity exerts on one kilogram at the Earth's surface. They share a name for historical reasons but they are different quantities and cannot be swapped. If you want to convert an amount of stuff, use the weight and mass converter. If you want to convert a push, pull or load, this is the right hub.
Is pound-force the same as a pound?
No. In everyday speech a pound is a mass, which is how it is used on a bathroom scale or in a recipe. Pound-force is specifically a unit of force, used in engineering for loads, thrust and test ratings. They are related through gravity but they measure different things, and treating them as identical is a common source of error when reading American engineering specs. Use this hub for pound-force and the weight converter for pounds of mass.
When would I use kilonewtons instead of newtons?
Whenever the numbers get large, which in structural and civil engineering is most of the time. A newton is a fairly small force, so building loads, cable tensions and structural ratings produce unwieldy figures in newtons and are quoted in kilonewtons instead. It is the same unit scaled by a thousand, so the conversion is a clean decimal shift with nothing to catch you out.
What is a dyne and is it still used?
The dyne is a very small unit of force from the older CGS system of units, which the SI system largely replaced. It survives in a few specific places, notably surface tension measurements and older physics literature, and you may meet it in materials science documentation. For anything modern, newtons are the standard, so converting a dyne figure is usually about reading an older or specialised source.