Popular conversions
1 pairsNewton ↔ Kilogram-Force
N ↔ kgf
Unit guides
2 unitsDetailed guide to Force
Force describes a push or pull that can change an object's motion. It is central to mechanics, structural engineering and everyday physics.
The newton is the SI derived unit of force, while kilogram-force is an older gravity-based unit still found in legacy technical documents and some measuring tools.
- Physical quantity
- Force
- SI unit
- Newton
- SI symbol
- N
- Formula
- F = m × a
- Typical use
- Mechanics, structural loads and material testing
Force is not mass
The newton is the SI unit of force. Pound-force and kilogram-force are force units, even though their names are often confused with units of mass in everyday language.
Use mass and acceleration when calculating force. A force conversion alone does not account for leverage, friction, dynamic loading or a safety factor.
What is force?
Force is defined by Newton's second law: F = m × a. One newton is the force needed to accelerate a 1-kilogram mass at 1 meter per second squared.
Force plays a central role in structural design, motion analysis and any calculation involving pushes, pulls or weight.
Newton and kilogram-force
One newton equals about 0.101972 kilogram-force. One kilogram-force equals exactly 9.80665 newtons, based on standard gravitational acceleration.
Kilogram-force predates the newton in engineering practice and still appears in older technical documents, torque wrenches and some measuring instruments.
Force, mass and pressure
Force divided by area gives pressure (N/m² = Pa), and force multiplied by distance gives energy (N·m = J) — the newton is the building block for both.
Mass and weight (force) are often confused in everyday language, but mass stays constant while weight depends on local gravitational acceleration.
Unit comparison table
| Unit | Symbol | SI equivalent | System | Common use |
|---|---|---|---|---|
| Newton | N | 1 N = 1 kg·m/s² | SI derived unit | Mechanics and engineering |
| Kilogram-Force | kgf | 1 kgf = 9.80665 N | Gravitational metric unit | Legacy equipment and load ratings |
Force units
| Unit | Symbol | Information |
|---|---|---|
| Newton | N | View unit guide |
| Kilogram-Force | kgf | View unit guide |