Stone to Kg Converter

The Stone to Kg Converter changes a body weight written in stone and pounds (st + lb) — the way weight is spoken in the United Kingdom and Ireland — into kilograms. Enter the whole stone and any loose pounds, for example 11 st 4 lb, and the tool returns the exact weight in kilograms along with grams, total pounds and decimal stone. A dual stone-and-kilogram weight beam shows where the weight lands, and a stacked "stone slab" visual makes it clear just how much a single stone actually weighs. You can also flip the tool around to convert kilograms back into stone and pounds.

How Many Kg Are in a Stone?

One stone is exactly 6.35029318 kilograms. This is not an approximation: a stone is defined as 14 pounds, and one pound is defined as exactly 0.45359237 kg, so 14 × 0.45359237 = 6.35029318 kg. For everyday mental maths, multiplying the number of stone by 6.35 gets you within a few grams.

Stone to Kg Formula

Converting stone and pounds to kilograms takes two short steps: first fold the compound weight into total pounds, then multiply by the kilogram factor.

For example, 11 st 4 lb becomes (11 × 14) + 4 = 158 lb, and 158 × 0.45359237 = 71.67 kg. Because the pound factor is exact, the only rounding is whatever you choose to keep in the final answer.

Stone to Kg Conversion Chart

What Is a Stone?

The stone is a traditional British unit of mass equal to 14 pounds. It remains in everyday use for personal body weight across the United Kingdom and Ireland, even though those countries otherwise use the metric system. People often find a compound figure such as "11 st 4 lb" easier to picture and compare than the equivalent 71.67 kg or 158 lb, which is why bathroom scales, gyms and doctors in those countries still report weight in stone and pounds.

Why Convert Stone to Kilograms?

• Medical forms and dosing: Most clinical guidelines, drug doses and BMI calculations use kilograms, so a stone-and-pounds weight must be converted first.
• Fitness and sport: Gym equipment, barbell plates and international competitions are almost always labelled in kilograms.
• Travel and paperwork: Airlines, visa forms and international documents expect metric weights.
• Sharing figures abroad: Friends and family outside the UK and Ireland will usually understand kilograms far more readily than stone.

How to Use This Calculator

1. Choose the direction: Leave it on "Stone + Pounds to Kg" to convert body weight into kilograms, or switch to "Kg to Stone + Pounds" to go the other way.
2. Enter the weight: Type the whole stone in the first box and any extra pounds in the second box — for example 11 stone and 4 pounds.
3. Click Convert: The tool instantly shows the weight in kilograms, grams, total pounds and decimal stone.
4. Explore the visuals: The weight beam shows where the weight sits, and each stone slab represents one stone (about 6.35 kg) so the number feels tangible.

Frequently Asked Questions

How many kg are in a stone?

One stone equals exactly 6.35029318 kilograms, because a stone is 14 pounds and a pound is defined as exactly 0.45359237 kg. For quick mental maths, multiply the stone by 6.35.

How do I convert stone and pounds to kg?

First turn the weight into total pounds by multiplying the stone by 14 and adding the loose pounds. Then multiply the total pounds by 0.45359237 to get kilograms. For example, 11 st 4 lb is (11 × 14) + 4 = 158 lb, and 158 × 0.45359237 = 71.67 kg.

What is 11 stone in kg?

11 stone is 154 pounds, which equals 69.85 kg. Adding 4 pounds to make 11 st 4 lb gives 158 pounds, or 71.67 kg.

Why is body weight measured in stone?

Stone is a traditional British unit still widely used for personal body weight in the United Kingdom and Ireland. People find compound figures like 11 st 4 lb easier to picture than 71.67 kg or 158 lb, so bathroom scales and doctors in those countries often report weight in stone and pounds.

Is one stone always 14 pounds?

For body weight, yes. The modern stone is fixed at exactly 14 avoirdupois pounds. Historically the stone varied by trade and region from 8 to 24 pounds, but the 14-pound stone is the only one in everyday use today.

How do I convert kg back to stone?

Switch the direction selector to "Kg to Stone + Pounds" and enter the kilograms. The tool divides by 0.45359237 to get total pounds, then splits that into whole stone (the pounds divided by 14, rounded down) and the leftover pounds.

Additional Resources

• Stone (unit) - Wikipedia
• Pound (mass) - Wikipedia