Convert stones and pounds to kilograms, or kg to stones and pounds. Our accurate UK weight converter includes a BMI calculator and NHS healthy weight guidelines. Perfect for tracking body weight, fitness goals, or understanding international weight measurements.
Calculate your Body Mass Index using your weight in stones and height
The NHS uses BMI (Body Mass Index) to assess whether adults are a healthy weight for their height. Here are the standard categories:
| BMI Range | Category | Health Risk |
|---|---|---|
| Under 18.5 | Underweight | Increased risk of nutritional deficiency |
| 18.5 - 24.9 | Healthy Weight | Lower risk of weight-related conditions |
| 25 - 29.9 | Overweight | Increased risk of health problems |
| 30 - 34.9 | Obese Class I | High risk of health problems |
| 35 - 39.9 | Obese Class II | Very high risk |
| 40+ | Obese Class III | Extremely high risk |
Note: BMI is a general guide. It doesn't account for muscle mass, age, gender, or ethnicity. Athletes may have a high BMI but low body fat. Consult your GP for personalized health advice.
These ranges show healthy weights (BMI 18.5-24.9) for different heights. Use as a general guide only.
| Height | Healthy Range |
|---|---|
| 5'0" (152 cm) | 6st 11lb - 9st 2lb (43-58 kg) |
| 5'2" (157 cm) | 7st 2lb - 9st 9lb (45-61 kg) |
| 5'4" (163 cm) | 7st 7lb - 10st 2lb (48-65 kg) |
| 5'6" (168 cm) | 8st 0lb - 10st 10lb (51-68 kg) |
| 5'8" (173 cm) | 8st 7lb - 11st 4lb (54-72 kg) |
| 5'10" (178 cm) | 9st 0lb - 12st 0lb (57-76 kg) |
| Height | Healthy Range |
|---|---|
| 5'6" (168 cm) | 8st 6lb - 11st 5lb (53-72 kg) |
| 5'8" (173 cm) | 8st 13lb - 12st 0lb (57-76 kg) |
| 5'10" (178 cm) | 9st 6lb - 12st 9lb (60-80 kg) |
| 6'0" (183 cm) | 10st 0lb - 13st 5lb (64-85 kg) |
| 6'2" (188 cm) | 10st 8lb - 14st 2lb (67-90 kg) |
| 6'4" (193 cm) | 11st 2lb - 14st 13lb (71-95 kg) |
Quick reference table for common stone to kilogram conversions:
| Stones | Kilograms | Pounds | Use |
|---|---|---|---|
| 5 stone | 31.75 kg | 70 lbs | Child/small adult |
| 6 stone | 38.10 kg | 84 lbs | Teen/petite adult |
| 7 stone | 44.45 kg | 98 lbs | Small adult |
| 8 stone | 50.80 kg | 112 lbs | Average woman |
| 9 stone | 57.15 kg | 126 lbs | Average woman |
| 10 stone | 63.50 kg | 140 lbs | Average adult |
| 11 stone | 69.85 kg | 154 lbs | Average man |
| 12 stone | 76.20 kg | 168 lbs | Average man |
| 13 stone | 82.55 kg | 182 lbs | Larger man |
| 14 stone | 88.90 kg | 196 lbs | Larger man |
| 15 stone | 95.25 kg | 210 lbs | Large frame |
| 16 stone | 101.60 kg | 224 lbs | Large frame |
| 17 stone | 107.95 kg | 238 lbs | Very large |
| 18 stone | 114.30 kg | 252 lbs | Very large |
| 20 stone | 127.00 kg | 280 lbs | Very large |
| 25 stone | 158.76 kg | 350 lbs | Extreme |
Convert common kilogram weights to stones and pounds:
| Kilograms | Stone & Lbs |
|---|---|
| 50 kg | 7 st 12 lbs |
| 55 kg | 8 st 9 lbs |
| 60 kg | 9 st 6 lbs |
| 65 kg | 10 st 3 lbs |
| 70 kg | 11 st 0 lbs |
| 75 kg | 11 st 11 lbs |
| Kilograms | Stone & Lbs |
|---|---|
| 80 kg | 12 st 8 lbs |
| 85 kg | 13 st 5 lbs |
| 90 kg | 14 st 2 lbs |
| 95 kg | 14 st 13 lbs |
| 100 kg | 15 st 10 lbs |
| 110 kg | 17 st 5 lbs |
Enter weight in any field (stones, pounds, or kilograms) and the converter automatically calculates the other units in real-time. For stone to kg: enter stones and pounds separately. For kg to stones: the result shows full stones plus remaining pounds. Conversions are based on official UK measurement standards: 1 stone = 14 pounds = 6.35029 kilograms exactly.
Example: 10 stone = 10 × 6.35029 = 63.5 kg
For stones and pounds: divide pounds by 14 to get stone fraction, add to whole stones, then multiply by 6.35029.
Example: 10 stone 7 pounds = (10 + 7÷14) × 6.35029 = (10 + 0.5) × 6.35029 = 66.68 kg
Example: 70 kg ÷ 6.35029 = 11.024 stone
To convert decimal to pounds: multiply by 14. Example: 0.024 × 14 = 0.34 pounds, so 70 kg = 11 stone 0.3 pounds.
Stone has been used in Britain since the 1300s for weighing goods and livestock. The imperial system standardized 1 stone = 14 pounds in 1389. Despite UK officially adopting metric system in 1965 for trade, stones remain dominant for body weight due to cultural tradition. Most UK bathroom scales show both stones/pounds and kilograms. NHS uses both units in health guidance. Only UK and Ireland use stones regularly - rest of world uses kilograms exclusively for body weight.
Last updated: January 2026 | Verified with latest UK rates
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