Pounds to Kilograms Converter

About the lb to kg calculation

One pound is exactly 0.453592 kilograms, so converting between them is a single multiplication. Enter any value above and the result updates as you type. The everyday US weight unit. Defined as exactly 0.45359237 kg since 1959. The SI base unit of mass, and how bodyweight is quoted in most of the world.

Formula

kg = lb × 0.453592

1 lb = 0.453592 kg
1 kg = 2.2046 lb

Worked example

To convert 150 lb, multiply by 0.453592: 150 × 0.453592 = 68.0389 kg.

Frequently asked questions

How many kilograms are in a pound?

There are 0.453592 kilograms in one pound. To convert any amount, multiply the number of pounds by 0.453592.

How do I convert kilograms back to pounds?

Divide instead of multiplying, or equivalently multiply by 2.2046. One kilogram is 2.2046 pounds.

Is this conversion exact?

Yes. Since the international agreement of 1959, the relationship between pounds and kilograms is defined exactly rather than measured, so the only rounding here is in how many decimal places we show.

Where is each of these units used?

Pounds: the everyday US weight unit. Defined as exactly 0.45359237 kg since 1959. Kilograms: the SI base unit of mass, and how bodyweight is quoted in most of the world.

Sources

• NIST Special Publication 811 — Guide for the Use of the International System of Units