Stone to Kilograms Converter

The converter above is already set to stone and kilograms, so you only need to enter your number. The result updates as you type, and nothing is sent anywhere.

1. Type your value in the Value box, for example 12. Decimals and negative numbers are accepted.
2. Check that From shows stone and To shows kilograms. Both menus can be changed if you need a different pair.
3. Read the answer in the large result box. The note under it shows the exact factor used for one stone.
4. Press Copy result to put the answer on your clipboard, or Swap units to convert in the opposite direction.
5. Look at In every unit on the right to see the same amount in all the other weight units.

One stone is about 6.35029 kilograms, so the formula is kilograms = stone x 6.35029. Going the other way, one kilogram is about 0.157473 stone. A stone is 14 pounds, about 6.35 kilograms, and is still used for body weight in the UK and Ireland. The kilogram is the base unit of mass in the metric system and is used for body weight in most countries.

Worked examples with the same factor:

• 12 stone: 12 x 6.35029 = 76.2035 kilograms
• 30 stone: 30 x 6.35029 = 190.509 kilograms
• 120 stone: 120 x 6.35029 = 762.035 kilograms

Multiply by 6.35: 12 stone is about 76.2 kg.

To check the converter by hand, take 30 stone and apply the rule once: the result should be 190.509 kilograms. If you go back again with the reverse factor 0.157473 you land on 30 stone, which confirms that the two directions agree. Rounding the factor to fewer digits for mental math gives a result that is close but not identical, so use the tool when the last digits matter.

These reference values come from the same factor the converter uses, so they match what you see above. Use the table for common amounts, and the converter for anything else.

Pounds, ounces and stone belong to the avoirdupois system, while grams and kilograms belong to the metric system. Since 1959 the pound has been defined as exactly 0.45359237 kilograms in the United States and the Commonwealth, so conversions are exact rather than approximate. Shops, gyms, airlines and doctors each pick one system, which is why people switch between them so often.

Use the table as a sanity check rather than a substitute for the converter. The result must scale with the input: double the weight and the converted figure doubles. For anything that matters, such as a medicine dose or a shipping charge, read the unit printed on the scale or label first, because the same number means very different things in each system.

Stone and pounds appear on UK bathroom scales and in older medical forms, while hospitals and international forms use kilograms.

Weight and mass are used interchangeably in everyday speech, and these units measure mass. The pound-mass and kilogram conversion is exact, but a kitchen scale can only show the precision it was built with, so do not trust more decimals than the scale gives. Also keep ounces of weight apart from fluid ounces of volume.

Related pages: Kilograms to Stone Converter for the reverse direction, and the pounds to kilograms and stone to pounds pages. For other weight units use the weight converter.

The page keeps no history, so each visit starts again from the defaults, 12 stone. Your numbers are processed by JavaScript in your own browser and are never sent to a server, which makes the converter safe for private figures such as medical, financial or work measurements.