mass conversion
Convert Pounds to Kilograms
One pound equals 0.45359 kilograms. Enter any value below for an exact conversion.
How to convert Pounds to Kilograms
- Type the number of pounds into the first field.
- The equivalent in kilograms appears immediately.
- Swap the units to convert in the opposite direction.
Pounds to Kilograms formula
kg = lb × 0.45359
Worked example: to convert 12 lb, multiply 12 × 0.45359 = 5.4431 kg.
This conversion factor is exact by international definition rather than measured, so the only rounding is whatever you apply to the final answer.
Pounds to Kilograms conversion table
| Pounds | Kilograms |
|---|---|
| 1 lb | 0.45359 kg |
| 2 lb | 0.90718 kg |
| 5 lb | 2.268 kg |
| 10 lb | 4.5359 kg |
| 25 lb | 11.3398 kg |
| 50 lb | 22.6796 kg |
| 100 lb | 45.3592 kg |
What is a pound?
The international avoirdupois pound has been defined as exactly 0.45359237 kilograms since the 1959 agreement between the US, UK, Canada, Australia, New Zealand and South Africa.
What is a kilogram?
The kilogram is the SI base unit of mass. Since 2019 it has been defined by fixing the Planck constant, replacing the platinum-iridium cylinder held near Paris since 1889.
Frequently asked questions
How many kilograms are in a pound?
One pound is 0.45359 kilograms.
How do I convert pounds to kilograms in my head?
Halve it and subtract 10%. 150 lb → 75 − 7.5 = 67.5 kg, about half a kilo under the exact 68.04.
Is the conversion exact?
Yes. Both units are defined in terms of each other by international agreement, so the factor 0.45359 is exact rather than approximate.
How many pounds is 100 kg?
100 kg is 220.46 lb.
Which countries use kilograms?
Every country except the United States, Liberia and Myanmar uses kilograms as the primary unit of mass.
Is my data uploaded to convert it?
No. The arithmetic runs in your browser. Nothing is sent anywhere.