Enter a value, choose the units to convert from and to, and see the result at once, with the same value in every other unit.
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For scale.
| Object | Mass |
|---|---|
| Milky Way galaxy | 1.15357 × 1042 kg |
| The Sun | 1.9891 × 1030 kg |
| Earth | 5.9736 × 1024 kg |
| The Moon | 7.3477 × 1022 kg |
| Proton | 1.6726 × 10-27 kg |
| Neutron | 1.6749 × 10-27 kg |
| Electron | 9.1094 × 10-31 kg |
Every unit in the list is defined as a fixed number of kilograms. To convert, the calculator turns your value into kilograms and then divides by the size of the unit you want. For example, 1 pound is exactly 0.45359237 kilogram, so 2.5 pounds is 1.133980925 kilograms, and since there are 16 ounces in a pound, 2.5 pounds is 40 ounces. Results are shown to about 10 significant digits.
In everyday speech weight and mass are used for the same thing, and the units in this converter are all units of mass. Strictly, mass is the amount of matter, while weight is the force of gravity on it. The kilogram is the SI unit of mass. Pounds and ounces are used in the US and in some other places, and the stone is still common in the UK and Ireland for body weight.
Several words mean different amounts in different places. A US, or short, ton is 2,000 pounds. A UK, or long, ton is 2,240 pounds. A metric ton is 1,000 kilograms. The US quarter is 25 pounds, the UK quarter is 28 pounds, and the stone is 14 pounds in the UK. A US stone, which is rarely used, is half of a US quarter, or 12.5 pounds. A carat, used for gems, is 0.2 gram, and a grain is 64.79891 milligrams.
Early weights were set by what a container could hold, or by the weight of seeds and stones. The carat comes from the carob seed, and the grain from a grain of barley. Over the centuries the Babylonian, Greek, Roman and Arabic systems blended, and the English pound and ounce came out of that history. Today every unit is defined from the kilogram, which makes exact conversion possible.
One kilogram is about 2.2046 pounds. Multiply kilograms by 2.2046226 to get pounds.
There are 16 ounces in a pound.
A UK stone is 14 pounds, or about 6.35 kilograms.
A short ton is 2,000 pounds, about 907 kilograms. A metric ton is 1,000 kilograms, about 2,205 pounds.
There are 5 metric carats in a gram, because one carat is 0.2 gram.
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