Force Converter: N, kN, lbf, kgf, dyne & More
Convert force between newton (N), kilonewton (kN), pound-force (lbf), kilogram-force (kgf), kip (kipf), dyne, metric / US / UK ton-force, SI prefixes from attonewton to exanewton, and joule per meter (same dimension as N). This converter uses the newton as the internal SI base so results match engineering and physics conventions. Free, runs in your browser—no sign-up required.
What is force?
Force is what changes motion (Newton’s second law: F = ma). The SI unit is the newton (N): 1 N = 1 kg·m/s². In practice you also see kN in structural engineering, lbf and kip (1000 lbf) in US specs, kgf (kilogram-force) and gf in older metric contexts, metric ton-force (tf), short and long ton-force, and the cgs unit dyne (1 dyn = 10⁻⁵ N). Joule per meter is equivalent to a newton because work per distance has the same dimension as force.
Gravitational units like kgf are defined using standard gravity g₀ = 9.80665 m/s². Pound-force uses the standard international foot–pound–second definition. Poundal and pound·foot/square second are the same imperial unit of force (1 lb accelerated at 1 ft/s²).
How force conversion works
Every unit is stored as its value in newtons. Multiply your input by the source unit’s N-factor, then divide by the target unit’s N-factor:
Example: 1 kip to kN. 1 kip = 1000 lbf ≈ 4448.22 N ≈ 4.448 kN. 100 kgf to N: 100 × 9.80665 = 980.665 N.
Key force units explained
Factors are newtons per one unit of the named force.
Newton (N)
Factor: 1 (SI unit)
1 N = 1 kg·m/s². Coherent with pascals (Pa = N/m²) and joules (J = N·m).
Pound-force (lbf)
Factor: 1 lbf ≈ 4.44822 N
US/UK engineering, loads, bolt tension. 1 kip = 1000 lbf.
Kilogram-force (kgf)
Factor: 1 kgf = 9.80665 N
Weight of 1 kg in standard gravity. Same magnitude as kilopond (kp).
Dyne (dyn)
Factor: 1 dyn = 10⁻⁵ N
CGS unit; still appears in older texts and surface-science contexts.
Metric ton-force (tf)
Factor: 1 tf = 1000 kgf ≈ 9806.65 N
Not mass: it is the force from 1000 kg in standard gravity.
Joule per meter (J/m)
Factor: 1 J/m = 1 N
Energy gradient per length; dimensionally identical to newton. J/cm equals 100 N.
When to use N vs lbf vs kgf
Use N and kN for SI calculations, structural codes that use SI, and physics. Use lbf and kip for US structural drawings, bolt specs, and machinery rated in pounds. Use kgf / tf where older metric practice or regional standards still quote “kilograms of force.” Always separate mass (kg) from force (N) in strict SI—even though “kgf” borrows the kilogram name, it is a force unit.
Who uses a force converter?
Structural and mechanical engineers switch between kN, lbf, and kip for reactions and member forces. Physicists and students convert dynes to newtons or compare SI prefixes. HVAC and lifting contexts may mix lbf with N on datasheets. Anyone comparing US and metric equipment ratings can normalize to newtons first. All conversions run locally in your browser.
Common force conversions at a glance
Quick reference; use the tool above for exact factors.
| From | To | Formula | Example |
|---|---|---|---|
| lbf | N | × 4.44822 | 100 lbf ≈ 444.8 N |
| kN | lbf | × 224.809 | 10 kN ≈ 2248 lbf |
| kgf | N | × 9.80665 | 1 kgf = 9.80665 N |
| kip | kN | × 4.44822 | 1 kip ≈ 4.448 kN |
| dyn | N | × 10⁻⁵ | 10⁶ dyn = 10 N |
Avoiding common mistakes
Don’t confuse mass (lbm, kg) with force (lbf, N) in strict SI—multiply mass by local g to get weight force when needed. Short ton-force (2000 lbf) differs from long ton-force (2240 lbf) and from metric ton-force (1000 kgf). Kip is 1000 lbf, not mass. If a label says “kg” but means “kgf,” treat it as force using this converter’s kgf row.
Force Conversion FAQ
? How many newtons are in one pound-force?
1 lbf ≈ 4.4482216152605 N. To convert lbf to N, multiply by 4.44822. To convert N to lbf, divide by 4.44822.
? What is a kip?
A kip (kip-force, kipf) is 1000 pound-force: 1 kip = 1000 lbf ≈ 4448.22 N. Common in US structural engineering for loads and reactions.
? Is kilogram-force the same as a kilogram of mass?
No. A kilogram (kg) is mass. Kilogram-force (kgf) is the force exerted by standard gravity on 1 kg mass: 1 kgf = 9.80665 N. The same numerical idea is called kilopond (kp) in some languages.
? How do you convert dynes to newtons?
1 dyne = 10⁻⁵ N. Multiply dynes by 10⁻⁵ to get newtons, or divide newtons by 10⁻⁵ to get dynes.
? Is joule per meter the same as a newton?
Yes: 1 J/m = 1 N, because joule is N·m. Joule per centimeter is 100 N (same energy per shorter distance implies larger force).