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| Kilograms | Stone |
|---|---|
| 50 kg | 7.87 st |
| 55 kg | 8.66 st |
| 60 kg | 9.45 st |
| 65 kg | 10.24 st |
| 70 kg | 11.02 st |
| 75 kg | 11.81 st |
| 80 kg | 12.60 st |
| 85 kg | 13.39 st |
| 90 kg | 14.17 st |
| 100 kg | 15.75 st |
| Stone | Kilograms |
|---|---|
| 8 st | 50.80 kg |
| 9 st | 57.15 kg |
| 10 st | 63.50 kg |
| 11 st | 69.85 kg |
| 12 st | 76.20 kg |
| 13 st | 82.55 kg |
| 14 st | 88.90 kg |
| 15 st | 95.25 kg |
| 16 st | 101.60 kg |
| 20 st | 127.01 kg |
A stone is a traditional British unit of weight equal to 14 pounds or 6.35029 kilograms. It's been used in the UK for centuries and remains the preferred unit for measuring human body weight, even though the metric system was officially adopted in 1965.
The stone measurement has historical roots dating back to medieval times when different regions had varying definitions. The standardization to 14 pounds occurred in the 14th century and has remained constant since then.
Kilograms to Stone:
Stone = Kilograms ÷ 6.35029
Stone to Kilograms:
Kilograms = Stone × 6.35029
Stone and Pounds to Kilograms:
Kilograms = (Stone × 6.35029) + (Pounds × 0.453592)
The NHS uses BMI (Body Mass Index) to assess healthy weight ranges. While healthcare professionals typically use kilograms, understanding your weight in stone can be helpful for everyday tracking:
For a 5'9" (175cm) adult, healthy weight ranges from approximately 9 stone (57kg) to 12 stone 7 pounds (79kg). However, these are general guidelines - factors like muscle mass, bone density, and overall health should also be considered.
UK healthcare settings primarily use metric measurements:
Most UK bathroom scales display both units. Track progress in whichever unit feels most natural, but be consistent for accurate comparison.
NHS patient records use kilograms. Know both your kg and stone weight for consultations.
Gym equipment and fitness apps often use kg. Stone is useful for long-term tracking and discussing progress with others.
The stone has been used in Britain since at least the 14th century. Originally, different commodities had different stone weights - wool was measured in 14-pound stones, while meat used 8-pound stones. The 14-pound stone became standard for human body weight.
Despite the UK officially adopting the metric system in 1965, stone remains deeply embedded in British culture. A 2020 survey found that over 70% of UK adults prefer to express their body weight in stone and pounds rather than kilograms.
When monitoring weight changes, small measurements matter:
Your weight can fluctuate by 2-4 pounds (0.9-1.8 kg) daily due to water retention, food intake, and hormonal changes. For accurate tracking, weigh yourself at the same time of day, ideally in the morning before eating.
The stone is unique to the UK and Ireland. When traveling or working internationally:
Our calculator uses the precise conversion factor of 1 stone = 6.35029318 kilograms. For practical purposes:
The NHS provides growth charts (centile charts) for children using both kilograms and stone/pounds. Parents should track their child's weight regularly:
The NHS recommends weight monitoring during pregnancy. Average healthy weight gain:
One stone equals exactly 6.35029 kilograms. This is the official conversion rate used throughout the UK for weight measurements.
To convert kg to stone and pounds: 1) Divide kilograms by 6.35029 to get stones. 2) Multiply the decimal part by 14 to get pounds. For example, 70kg = 11.02 stone = 11 stone 0.3 pounds.
The NHS recommends maintaining a healthy BMI between 18.5 and 24.9. For a person 5'9" tall, this translates to roughly 9 stone to 12 stone 7 pounds (57-79 kg). Check with your GP for personalized advice.
The UK uses stone as a traditional unit of measurement dating back centuries. While officially metric since 1965, stone remains popular for measuring body weight. One stone equals 14 pounds or 6.35029 kilograms.
This calculator uses the exact conversion factor (1 stone = 6.35029318 kg) and provides results accurate to 2 decimal places, which is more than sufficient for all practical weight measurements.
Yes, this calculator works for all weights including newborns. UK babies are typically weighed in kilograms by healthcare professionals, but parents often prefer to know the weight in pounds and ounces.
A stone is a larger unit of weight equal to 14 pounds. In the UK, body weight is commonly expressed as a combination of stones and pounds (e.g., 10 stone 7 pounds) rather than just pounds.
Yes, stone remains widely used in the UK for measuring personal body weight, despite official metrication. Most UK bathroom scales show both kilograms and stone/pounds, and it's the preferred unit in everyday conversation.
✓ Expert Reviewed — This calculator is reviewed by our team of financial experts and updated regularly with the latest UK tax rates and regulations. Last verified: January 2026.
Last updated: January 2026 | Verified with latest UK rates