LBS to KG Converter

Multiply the pounds by 0.45359237. This is the definition of the pound, not a measured value, so the product is the exact weight in kilograms; you only round at the end for display.

Someone weighing 185 lb is 185 × 0.45359237 = 83.91 kg. Medical forms in metric countries usually want one decimal, so write 83.9 kg. For a 20 lb turkey the same step gives 9.07 kg, and for a 50 lb sack of dog food 22.68 kg.

If your weight is in stone and pounds (UK style), turn the stone into pounds first by multiplying by 14, add the loose pounds, then multiply the total by 0.45359237.

Halve the pounds, then take away a tenth of the half. For 185 lb: half is 92.5, a tenth of that is about 9.3, and 92.5 − 9.3 = 83.2 kg. The exact answer is 83.9, so this trick runs slightly under, by roughly 1%.

Dividing by 2.2 is closer still: 185 ÷ 2.2 = 84.1 kg, about a fifth of a percent high. A simple sanity check is that 100 lb is about 45 kg and 200 lb about 91 kg.