Divide by 14, and the remainder is the extra pounds
One stone is 14 pounds, so the whole number of stone is the pounds divided by 14, and whatever is left over becomes the pounds part. UK and Irish body weight is nearly always given this way, as stone-and-pounds rather than a single number.
To reach kilograms instead, multiply the pounds by 0.4536 — or take the stone and multiply by 6.35.
Quick reference — body weight
| Pounds | Stone & pounds | Kilograms |
|---|---|---|
| 120 lb | 8 st 8 lb | 54.4 kg |
| 140 lb | 10 st 0 lb | 63.5 kg |
| 154 lb | 11 st 0 lb | 69.9 kg |
| 160 lb | 11 st 6 lb | 72.6 kg |
| 180 lb | 12 st 12 lb | 81.6 kg |
| 200 lb | 14 st 4 lb | 90.7 kg |
Each whole stone is 6.35 kg, so 10 st is 63.5 kg and every extra pound adds about 0.45 kg.
Where stone is used, and where it is not
- Body weight only. Stone is the everyday and clinical weight unit in the UK and Ireland, but it is not used for anything else — you would not weigh luggage or groceries in stone.
- Not in North America. The US and Canada use pounds and kilograms. Stone is recognised there but almost never used, so state weight to a US audience in pounds.
- Stone is always 14 pounds now. Historically local "stones" ranged from 5 to 40 pounds by trade and region; the 14-pound stone is the only one still in use.
Common questions
How many pounds are in a stone?
Exactly 14 pounds. The stone has been fixed at 14 pounds in British trade since a statute of Edward III in 1350, and that is still the definition today.
How do I convert pounds to stone and pounds?
Divide the pounds by 14 to get the whole stone, then the leftover is the extra pounds. 160 lb is 160 divided by 14 = 11 with 6 left over, so 11 stone 6 pounds.
How much is one stone in kilograms?
About 6.35 kg (14 pounds times 0.4536). To go from stone straight to kilograms, multiply the number of stone by 6.35.
