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. NHS healthy weight range for most adults: approximately 8–13 stone (50–82 kg).
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.
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. NHS healthy weight range for most adults: approximately 8–13 stone (50–82 kg).
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.