1 Stone to KG: How Many KG to a Stone? (Stone, Pounds and KG)

1 stone is 6.35 kg. The exact figure is 6.35029318 kg, and it is the same as 14 pounds. To convert 1 stone to kg, or any number of stone, multiply by 6.35029.

This is the one number behind every stone and kilogram conversion. Once you know it, you can work out any body weight in either unit. The rest of this page explains where the number comes from and how to use it.

How many kg are in a stone?

There are 6.35 kilograms in one stone. For most purposes two decimal places are enough, but the full value is 6.35029318 kg.

The figure is exact, not measured. A stone is defined as 14 pounds, and a pound is defined as 0.45359237 kg. Multiply the two and you get 6.35029318. Because both parts are fixed by definition, the answer never changes.

In grams, one stone is 6,350 g. In ounces, it is 224 oz.

How do you convert 1 stone to kg and back again?

To go from stone to kilograms, multiply by 6.35029. To go from kilograms to stone, divide by 6.35029.

Here are both directions with easy numbers:

• 1 stone × 6.35029 = 6.35 kg
• 3 stone × 6.35029 = 19.05 kg
• 20 kg ÷ 6.35029 = 3.15 stone
• 50 kg ÷ 6.35029 = 7.87 stone

When a weight has pounds as well as stone, change everything to pounds first. Multiply the stone by 14, add the spare pounds, and multiply the total by 0.453592. For 1 stone 5 pounds, that is 19 pounds, which comes to 8.62 kg.

What are 1 to 10 stone in kg?

Each stone adds another 6.35 kg. The table shows the first ten.

Stone	Kilograms	Pounds
1 st	6.35 kg	14 lb
2 st	12.70 kg	28 lb
3 st	19.05 kg	42 lb
4 st	25.40 kg	56 lb
5 st	31.75 kg	70 lb
6 st	38.10 kg	84 lb
7 st	44.45 kg	98 lb
8 st	50.80 kg	112 lb
9 st	57.15 kg	126 lb
10 st	63.50 kg	140 lb

Notice that 10 stone comes out at a neat 63.5 kg. Many people use that as a fixed point and count up or down from it.

What is half a stone or a quarter of a stone in kg?

Half a stone is 3.18 kg and a quarter of a stone is 1.59 kg. These smaller amounts come up often when people talk about weight loss.

Part of a stone	Pounds	Kilograms
Quarter of a stone	3.5 lb	1.59 kg
Half a stone	7 lb	3.18 kg
Three quarters of a stone	10.5 lb	4.76 kg
One stone	14 lb	6.35 kg
A stone and a half	21 lb	9.53 kg
Two stone	28 lb	12.70 kg

A single pound is 0.45 kg. So if someone says they have lost “a stone and three pounds”, that is 6.35 plus 1.36, which makes 7.71 kg.

How many stone is 1 kg?

One kilogram is 0.157 stone, or about 2.2 pounds. It takes a little over six kilograms to make a stone.

This is the reverse of the main conversion and is useful for small changes. A 2 kg loss is 4.4 pounds. A 5 kg loss is 11 pounds, which is just over three quarters of a stone. A 10 kg loss is 1 stone 8 pounds.

Why does a stone have 14 pounds?

The 14-pound stone comes from the medieval English wool trade. Wool was the country’s most valuable export, and a royal law in the 1300s set the stone of wool at 14 pounds.

Before that, a “stone” was whatever weight a local market agreed on. Traders really did use stones as weights on their scales, and the size changed with the goods. Meat, glass, spices and wool each had their own stone, ranging from about 5 pounds to well over 20. A sack of wool was fixed at 26 stone, so getting the stone right mattered a great deal for trade and tax.

Over time the wool stone won out. In the 1800s, weights and measures law made 14 pounds the one official stone across Britain. It stopped being a legal unit for trade in the 1980s, but people have kept using it for body weight ever since.

Which countries still use stone?

The UK and Ireland are the only countries where stone is in everyday use, and only for body weight.

In Britain, a person might buy petrol in litres, run a race in kilometres, order a pint of beer and give their weight in stone, all on the same day. Older people in Australia and New Zealand may remember stone from before those countries switched to metric. In the United States and Canada, body weight is given in pounds alone, and most Americans have never heard the unit used.

Everywhere else, weight is in kilograms. That is why anyone travelling, moving abroad or filling in an international form needs to know that a stone is 6.35 kg.

How is the kilogram different from the stone?

The kilogram is the world’s standard unit of mass, and the stone is a traditional British unit built from pounds. One is part of the metric system and the other is part of the imperial system.

The metric system works in tens. A kilogram is 1,000 grams and a tonne is 1,000 kilograms, so moving between units only means shifting a decimal point. The imperial system uses mixed steps. There are 16 ounces in a pound, 14 pounds in a stone and 8 stone in a hundredweight. That is why imperial sums feel harder.

Scientists define the kilogram using a fixed constant of nature, so it is the same in every laboratory on Earth. The pound, and therefore the stone, is now defined from the kilogram. In other words, the stone depends on the kilogram and not the other way round.

How do bathroom scales switch between stone and kg?

Digital scales measure your weight once and then show it in whichever unit you choose. Inside, most work in kilograms and convert the result for the display.

When you press the unit button, the scales divide by 6.35029 and show stone and pounds. In effect they do the 1 stone to kg sum in reverse, every time you step on. Switching units does not make the reading more or less accurate. The steps on the display may differ, though. Many scales move in steps of 0.1 kg in metric mode and 0.2 pounds in imperial mode.

How heavy is one stone in everyday terms?

One stone weighs about the same as six and a third one-litre bottles of water. A litre of water is one kilogram, so 6.35 litres is one stone.

Some other ways to picture it:

• Fourteen standard 454 g jars of jam, since each jar holds one pound.
• Six bags of sugar at 1 kg each, with a little extra.
• A bit less than a heavy tenpin bowling ball, which weighs 16 pounds.
• Roughly a quarter of a 25 kg bag of cement.

Picking up something of this weight can be a good reminder of what losing a stone means for your knees and back.

What does losing a stone mean in kg?

Losing a stone means losing 6.35 kg. At a steady pace of 0.5 to 1 kg a week, that takes about six to thirteen weeks.

How big that loss is depends on where you start. For someone who weighs 10 stone, one stone is 10% of their body weight. For someone who weighs 14 stone, it is about 7%. For someone at 20 stone, it is 5%. Health advice often points to 5% as a worthwhile first goal for people who are overweight, so a single stone can make a real difference at heavier weights.

Speak to your GP before aiming for a large loss, especially if you take regular medicine.

Is it “stone” or “stones”?

For body weight, the plural is “stone”. People say “I weigh eleven stone”, not “eleven stones”.

The short form is “st”, and pounds are written “lb”. A weight is usually written as “11 st 6 lb” or simply “11 st 6”. When spoken, the word pounds is often dropped, as in “eleven stone six”.

Frequently asked questions

Is 1 stone 6 kg or 7 kg?

It is 6.35 kg, so it is closer to 6. Rounding to 6 is fine for one stone but adds up to a large error for heavier weights.

How many pounds are in 1 stone?

There are 14 pounds in a stone.

What is 2 stone in kg?

Two stone is 12.7 kg.

What is 5 stone in kg?

Five stone is 31.75 kg.

How many grams are in a stone?

There are 6,350 grams in a stone.

How do I convert 1 stone to kg quickly?

Remember 6.35. For a larger number of stone, multiply by 6 and add a third of the stone figure. Nine stone is 54 plus 3, which gives 57 kg. The exact answer is 57.15 kg.

Does the answer for 1 stone to kg ever change?

No. The stone and the pound are fixed by definition, so one stone has been exactly 6.35029318 kg since the pound was set at its present value in 1959.

Is a UK stone different from a US stone?

There is no US stone. The unit is not used there. The pound is the same in both countries, so 1 stone is 14 pounds wherever you are.

What is the short answer?

One stone equals 6.35 kg, 14 pounds or 6,350 grams. Multiply stone by 6.35029 to get kilograms, and divide kilograms by 6.35029 to get stone. For anything with spare pounds, use the stone to kg converter on this site.