Convert Force from Newtons to Kilogram-forces (N to kgf)

Newton to Kilogram-force Conversion Formula

Example

Let's convert 5 Newton (N) to Kilogram-force (kgf).

Using the formula:

Therefore, 5 Newton (N) is equal to 0.5098399102681757928 Kilogram-force (kgf).

How many newtons are in one kilogram-force? One Kilogram-force (kgf) contains 9.807 Newtons (N) — the inverse of the factor above. Multiplying by 0.10196798205363515856 takes you from newtons to kilogram-forces; multiplying by 9.807 brings you back.

Put in words: one newton equals 0.10196798205363515856 kilogram-forces, so the newton is the smaller unit of this pair. Converting between them never changes the amount of force being measured — only the size of the unit you count it in.

What Is a Newton (N)?

A newton (N) is the SI unit of force. One newton is the force needed to accelerate a mass of one kilogram at one metre per second squared.

Written as a formula, that is 1 N = 1 kg·m/s².

What Does a Newton Feel Like?

A newton is a small amount of force in everyday terms. Holding a medium apple in your palm against gravity takes roughly 1 N. Lifting a 1 kg bag of sugar takes about 9.81 N, because gravity pulls on every kilogram with about 9.81 newtons of weight at the Earth's surface.

That last number is the reason force and mass are so easily confused. A kilogram is how much matter an object contains; a newton is how hard something pushes or pulls. The same 1 kg bag weighs about 9.81 N on Earth but only about 1.6 N on the Moon, while its mass never changes.

Where Newtons Are Used

• Structural engineering — loads on beams, columns and fasteners, usually in kilonewtons.
• Mechanical design — spring rates, clamping forces, bearing loads.
• Physics and education — every force problem in the SI system resolves to newtons.
• Test equipment — tensile testers, load cells and force gauges read directly in N.

Named After Isaac Newton

The unit honours Sir Isaac Newton and his second law of motion, F = ma. The name was adopted by the General Conference on Weights and Measures in 1948.

Note the capitalisation convention: the unit symbol is a capital N, but the unit name is written in lower case — newton, not Newton — as with all SI units named after people.

Quick Reference

What Is a Kilogram-force (kgf)?

A kilogram-force (kgf), also called a kilopond (kp), is the force exerted by gravity on a mass of one kilogram at standard gravity.

• 1 kgf = 9.807 N

A Metric Unit That Behaves Like an Imperial One

The kilogram-force is a gravitational metric unit: it takes the convenience of the imperial system — where the number on the scale and the number in the force calculation match — and applies it to metric mass. If a load is 250 kg, its weight is simply 250 kgf.

That convenience is also why the unit was deprecated. It bakes the Earth's gravity into the definition, so any calculation using it silently assumes you are standing on this planet at sea level. The SI system replaced it with the newton, and modern standards discourage kgf in new work.

Where You Still Meet It

Deprecated does not mean gone. Kilogram-force still appears in:

• Older machinery and technical drawings, particularly European and Japanese equipment made before the 1990s.
• Tyre and pressure gauges in some markets, where kgf/cm² is used instead of bar.
• Torque wrenches graduated in kgf·m or kgf·cm.
• Medical and fitness equipment — grip strength dynamometers commonly read in kgf.

If you are reading an old service manual, expect kgf. If you are writing a new specification, use newtons.

Converting Kilogram-force

Newton to Kilogram-force Conversion Table

Here are some quick reference conversions from Newton (N) to Kilogram-force (kgf):