Force Unit Converter
kN, N, tonne-force, kgf and lbf for loads and lifting.
Inputs
Result
Formula
| Base | 1 kN = 1000 N, 1 MN = 1000 kN |
| Gravity | 1 kgf = 9.80665 N, 1 tf = 9.80665 kN |
| Anglo-American | 1 lbf = 4.44822 N, 1 kip = 1000 lbf = 4.44822 kN |
| Mass and force | 1 t of mass produces 9.80665 kN of weight |
| Site rule | Take 1 t ≈ 10 kN, a 2% overestimate |
One tonne-force is 9.80665 kN, 1000 kgf or 2204.62 lbf. A sling rated 50 kN is about 5.1 tf; with a safety factor of 6 each leg may lift 0.85 t.
Force and load unit reference
| Unit | Symbol | In kN | In tonne-force | Typical use |
|---|---|---|---|---|
| Kilonewton | kN | 1 | 0.102 | Structural loads |
| Newton | N | 0.001 | 0.000102 | Small members |
| Dekanewton | daN | 0.01 | 0.00102 | European marking |
| Tonne-force | tf | 9.80665 | 1 | Lifting weights |
| Kilogram-force | kgf | 0.009807 | 0.001 | Old codes |
| Kip | kip | 4.44822 | 0.4536 | US structures |
| Pound-force | lbf | 0.004448 | 0.000454 | US customary |
FAQ
Why are loads in kN rather than kg?
The kilogram measures mass and the kilonewton measures force, and structures respond to force. The same one-tonne machine weighs 9.8 kN on Earth and 1.6 kN on the Moon. A code live load of 2.0 kN/m² is a force, about 204 kg/m² of mass — which is where the “200 kg per square metre” floor label comes from.
How do wire rope tonnages convert to kN?
Multiply by 9.80665. A rope rated 10 t has a breaking force near 98 kN; divide by the safety factor for working load — 6 for lifting, 14 for man-riding. Check whether the maker quotes breaking force or working load, because they differ sixfold and getting it wrong kills people.
How heavy is 1 kN really?
About 102 kg — one adult, or two bags of cement. On site, allow roughly 1 kN per 100 kg: a 6 m length of 25 mm bar is 23 kg or 0.23 kN, and a 1 m² plate 10 mm thick is 78.5 kg or 0.77 kN.
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Results are estimating aids only and are not a design basis. Construction and final accounts must follow the drawings, the applicable standards and an approved method statement. Anything affecting structural safety, shoring or falsework must be checked by a suitably qualified engineer.