Quick answer
Force units convert through newtons. 1 pound-force equals 4.4482 newtons, and 1 kilogram-force equals 9.80665 N.
Enter a value and choose the units. The calculator returns the converted force.
Related tools: Force Calculator: Force from mass and acceleration (Newton's second law). Gravitational Force Calculator: Newtonian gravitational attraction between two masses. Centripetal Force Calculator: Force and acceleration for circular motion.
How to use the Force Converter
- Enter value.
- Choose from: Newton (N), Millinewton (mN), Micronewton (µN), Kilonewton (kN), Meganewton (MN) and Pound-force (lbf) and 5 more.
- Choose to: Newton (N), Millinewton (mN), Micronewton (µN), Kilonewton (kN), Meganewton (MN) and Pound-force (lbf) and 5 more.
- Enter decimal places (between 0 and 10). It starts at 4.
- Press Calculate to see the result, and use Reset to start again.
| Input | What to enter | Allowed values |
|---|---|---|
| Value | A number | — |
| From | Choose one: Newton (N); Millinewton (mN); Micronewton (µN); Kilonewton (kN); Meganewton (MN); Pound-force (lbf); Ounce-force (ozf); Kilogram-force (kgf); … | Starts at Newton (N) |
| To | Choose one: Newton (N); Millinewton (mN); Micronewton (µN); Kilonewton (kN); Meganewton (MN); Pound-force (lbf); Ounce-force (ozf); Kilogram-force (kgf); … | Starts at Millinewton (mN) |
| Decimal places | A number | ≥ 0, ≤ 10, starts at 4 |
Formula and method
Formula
result = value × (factor of source ÷ factor of target), base unit: newton
IEEE-754 double precision; displayed to the chosen number of decimal places (default 4). Very small or large results are shown in scientific notation.
Every unit is defined by an exact or published factor to the base unit (newton). The value is multiplied by the source factor and divided by the target factor.
Worked examples
These examples are verified: each one is an automated test case that the live calculator must reproduce exactly.
Example 1
Inputs: Value = 1; From = Pound-force (lbf); To = Newton (N); Decimal places = 4.
| Result | Value |
|---|---|
| Pound-force (lbf) → Newton (N) | 4.4482 |
| Input | 1 Pound-force (lbf) |
Example 2
Inputs: Value = 1; From = Kilogram-force (kgf); To = Newton (N); Decimal places = 5.
| Result | Value |
|---|---|
| Kilogram-force (kgf) → Newton (N) | 9.80665 |
| Input | 1 Kilogram-force (kgf) |
Example 3
Inputs: Value = 1; From = Kilonewton (kN); To = Newton (N); Decimal places = 4.
| Result | Value |
|---|---|
| Kilonewton (kN) → Newton (N) | 1,000 |
| Input | 1 Kilonewton (kN) |
The first line is the headline result (pound-force (lbf) → Newton (N)). Below it the force Converter lists input, which describe the same case from other angles. IEEE-754 double precision; displayed to the chosen number of decimal places (default 4). Very small or large results are shown in scientific notation.
Unit reference
Each unit expressed in the base unit used for the calculation. Conversions go through this base unit, so any unit can be converted to any other in the table.
| Unit | Equals (in newton) |
|---|---|
| Newton (N) | 1 |
| Millinewton (mN) | 0.001 |
| Micronewton (µN) | 0.000001 |
| Kilonewton (kN) | 1000 |
| Meganewton (MN) | 1000000 |
| Pound-force (lbf) | 4.448221615 |
| Ounce-force (ozf) | 0.278013851 |
| Kilogram-force (kgf) | 9.80665 |
| Dyne (dyn) | 0.00001 |
| Nanonewton (nN) | 1e-9 |
| Poundal (pdl) | 0.1382549544 |
Force versus mass
Pounds and kilograms are normally units of mass, while force units like the newton and pound-force include gravity. A 1 kg mass weighs about 9.81 N on Earth, which is also 1 kilogram-force.
Quick conversions
1 N = 0.2248 lbf = 100,000 dynes. 1 kN = 224.8 lbf. Use the newton for engineering calculations in SI.
How the result changes with value
Holding every other input at the first worked example, this table changes only value. It shows how sensitive the answer is to that one value; each row was produced by running this calculator.
| Value | Pound-force (lbf) → Newton (N) | Input |
|---|---|---|
| 0.5 | 2.2241 | 0.5 Pound-force (lbf) |
| 1 | 4.4482 | 1 Pound-force (lbf) |
| 2 | 8.8964 | 2 Pound-force (lbf) |
| 4 | 17.7929 | 4 Pound-force (lbf) |
What happens with invalid input
These messages are produced by the calculator itself, so you know what to fix.
- Value: left empty shows "Enter value." beside that field and no result.
Choosing between the Force Converter and similar calculators
Each row shows what a related calculator on this site asks for and what it returns, so you can pick the one that matches your question.
| Calculator | You enter | It returns |
|---|---|---|
| [Force Calculator](/science/force-calculator/) | mass and acceleration | Force |
| [Gravitational Force Calculator](/science/gravitational-force-calculator/) | mass 1, mass 2 and distance between centers | Gravitational force |
| [Centripetal Force Calculator](/science/centripetal-force-calculator/) | mass, speed and radius | Centripetal force |
| [Normal Force Calculator](/science/normal-force/) | mass, incline angle and gravitational acceleration | Normal force |
| [Net Force Calculator](/science/net-force-calculator/) | force magnitudes and direction of each force | Net force |
Background: unit conversion
Many customary units are defined exactly in terms of metric ones: since the 1959 International Yard and Pound Agreement an inch is exactly 2.54 cm and a pound is exactly 0.45359237 kg (NIST SP 811 lists these). So most length and mass conversions are exact apart from the rounding of the displayed result.
To convert, multiply the value by the source unit's factor to reach the base unit, then divide by the target unit's factor; the unit table on this page lists every factor used. Temperature and fuel economy are the exceptions, because they are not simple multiples.
Assumptions and limitations
- Negative values are allowed
- Zero converts to zero (except L/100 km, where zero is invalid)
- Units from different quantities cannot be converted
- Very large or tiny results switch to exponent notation
If a required value is empty, not a number, or outside its allowed range, the form marks that field with a message and shows no result instead of a misleading number. The automated checks deliberately try invalid entries for value to confirm this.
Frequently asked questions
How many newtons is 100 lbf?
100 pounds-force is about 444.8 N.
What is a kilonewton?
A kilonewton is 1,000 newtons; 1 kN is about 224.8 pounds-force.
Is kgf the same as kg?
No, kgf is a force, kg is a mass.
What does the Force Converter calculate?
Convert newtons, pounds-force, kilograms-force and dynes. It returns Pound-force (lbf) → Newton (N) and Input.
What formula does the Force Converter use?
result = value × (factor of source ÷ factor of target), base unit: newton. Every unit is defined by an exact or published factor to the base unit (newton).
What is an example of a force result?
With value 1, from Pound-force (lbf), to Newton (N) and decimal places 4, the pound-force (lbf) → Newton (N) is 4.4482.
Where does the method come from?
The method follows: NIST SP 811 (2008): standard gravity 9.80665 m/s² exactly; lbf = 4.4482216152605 N; dyne = 1e-5 N.
Related calculators
- Force Calculator — Force from mass and acceleration (Newton's second law).
- Gravitational Force Calculator — Newtonian gravitational attraction between two masses.
- Centripetal Force Calculator — Force and acceleration for circular motion.
- Normal Force Calculator — Normal force on an object resting on a flat or inclined surface.
- Net Force Calculator — Resultant of several forces at different angles.
- Friction Force Calculator — Friction force from the coefficient of friction and the normal force.
Sources
- NIST SP 811 (2008): standard gravity 9.80665 m/s² exactly; lbf = 4.4482216152605 N
- dyne = 1e-5 N
Content last reviewed 2026-11-04. Formulas and worked examples are checked by automated tests against independently computed values.