Stones vs Kilograms
Side-by-side comparison, when-to-use-each guide, and instant conversion. Reviewed for 2026.
UK and Ireland body weight (universally), some Commonwealth horse-racing.
Body weight everywhere outside UK/Ireland, all sports above amateur level, medical context worldwide (including the NHS for clinical work).
| Aspect | Stones | Kilograms |
|---|---|---|
| Unit size | 14 lbs / 6.35 kg | SI base unit |
| UK everyday use | Body weight only | Increasingly common, especially in gyms |
| UK NHS use | Patient self-reported | Clinical and prescription dosing |
| Conversion | ×6.35029 → kg | ×0.157473 → stones |
Frequently asked
How heavy is 12 stone in kg?
12 stone = 76.2 kg exactly (12 × 6.35029 kg). Common stone-to-kg values: 10st = 63.5 kg, 11st = 69.85 kg, 12st = 76.2 kg, 13st = 82.55 kg, 14st = 88.9 kg. What counts as a healthy weight depends on your height, so use the NHS BMI healthy weight calculator rather than a single stone range.
Do UK doctors use stones?
NHS clinical records use kg for prescribing and clinical decisions, but doctors will often discuss weight in stones because that's what patients understand.
Stone to kg and pounds chart
One stone is 14 pounds, or 6.35029 kg. To convert a weight given as stones and pounds (for example 11 st 4 lb), convert the stones to pounds, add the extra pounds, then multiply the total pounds by 0.453592 to get kilograms.
| Stones | Pounds | Kilograms |
|---|---|---|
| 6 st | 84 lb | 38.1 kg |
| 7 st | 98 lb | 44.5 kg |
| 8 st | 112 lb | 50.8 kg |
| 9 st | 126 lb | 57.2 kg |
| 10 st | 140 lb | 63.5 kg |
| 11 st | 154 lb | 69.9 kg |
| 12 st | 168 lb | 76.2 kg |
| 13 st | 182 lb | 82.6 kg |
| 14 st | 196 lb | 88.9 kg |
| 15 st | 210 lb | 95.3 kg |
| 16 st | 224 lb | 101.6 kg |
| 17 st | 238 lb | 108.0 kg |
| 18 st | 252 lb | 114.3 kg |
| 19 st | 266 lb | 120.7 kg |
| 20 st | 280 lb | 127.0 kg |
A healthy weight depends on height, age and build, so there is no single stone range that suits everyone. The NHS BMI healthy weight calculator gives a range for your height.
Frequently asked questions
How heavy is 12 stone in kg?
12 stone = 76.2 kg exactly (12 × 6.35029 kg). Common stone-to-kg values: 10st = 63.5 kg, 11st = 69.85 kg, 12st = 76.2 kg, 13st = 82.55 kg, 14st = 88.9 kg. What counts as a healthy weight depends on your height, so use the NHS BMI healthy weight calculator rather than a single stone range.
Do UK doctors use stones?
NHS clinical records use kg for prescribing and clinical decisions, but doctors will often discuss weight in stones because that's what patients understand.