Stone to KG Converter

Stone to KG chart

The 8–16 stone band covers most adult body weights (50.8–101.6 kg).

How this is calculated

kg = stone × 6.35029318 (exact — 14 lb per stone)

Stone is how bodies are weighed in the UK and Ireland: 11 stone is 69.85 kg, “12 st 7” (12 stone 7 pounds) is 79.38 kg. One stone is 14 pounds exactly, so the factor inherits the pound’s exact definition. Convert mixed stone-and-pound weights by adding pounds ÷ 14 first.

Exact: 14 × 0.45359237 kg = 6.35029318 kg per stone. Medical UK practice now records kilograms, but scales, gyms, and conversation still speak stone — this page is the translator.

Stone to kilograms is a British and Irish conversion almost nowhere else uses. One stone is exactly 14 pounds, or 6.35029 kg, and body weight is spoken as stone and pounds — "eleven stone four" — which is the source of the most common error in this direction: 11 stone 4 lbs is 11.286 stone, not 11.4.

Convert the stone and the pounds separately and add, or convert the whole thing to pounds first. Medical settings almost always work in kilograms, so this is the conversion that turns a familiar figure into the one on the chart — and the one that makes a change of a couple of kilograms look larger than the same change in stone.