Weight Converters
Weight (strictly speaking, mass) converters help you move between metric units like grams and kilograms and the pounds, ounces and stones that are still common in cooking, fitness and body weight in the US and UK. Whether you are reading a recipe, checking a baggage allowance or comparing gold and gemstone weights, the converters on this page use the internationally agreed definitions, such as one pound being exactly 0.45359237 kilograms.
All weight converters
Carats to Grams1 ct = 0.2 gGrams to Ounces1 g = 0.035274 ozKilograms to Pounds1 kg = 2.20462 lbKilograms to Stones1 kg = 0.157473 stMilligrams to Grams1 mg = 0.001 gOunces to Grams1 oz = 28.3495 gPounds to Kilograms1 lb = 0.453592 kgPounds to Ounces1 lb = 16 ozStones to Pounds1 st = 14 lbTonnes to Tons1 t = 1.10231 tonTons to Kilograms1 ton = 907.185 kg
Things to know about weight conversions
- Scientists call the quantity mass, but in everyday use it is called weight. The conversions here apply to both.
- The word "ton" can mean 2,000 pounds (US), 2,240 pounds (UK) or 1,000 kilograms (metric tonne). Always check which one a document uses.
- A carat measures gemstone weight (200 mg). Do not confuse it with karat, which describes gold purity.
- One stone equals exactly 14 pounds, and is still used for body weight in the UK and Ireland.
Weight conversion chart
Read across: one of the unit in the left column equals the value shown under each unit.
| 1 unit = | mg | g | kg | t | oz | lb | st | ton | long ton | ct |
|---|---|---|---|---|---|---|---|---|---|---|
| mg | 1 | 0.001 | 1 × 10-6 | 0 | 0.00003527 | 2.205 × 10-6 | 1.575 × 10-7 | 1.102 × 10-9 | 0 | 0.005 |
| g | 1,000 | 1 | 0.001 | 1 × 10-6 | 0.03527 | 0.002205 | 0.0001575 | 1.102 × 10-6 | 9.842 × 10-7 | 5 |
| kg | 1,000,000 | 1,000 | 1 | 0.001 | 35.27 | 2.205 | 0.1575 | 0.001102 | 0.0009842 | 5,000 |
| t | 1,000,000,000 | 1,000,000 | 1,000 | 1 | 35,274 | 2,205 | 157.5 | 1.102 | 0.9842 | 5,000,000 |
| oz | 28,350 | 28.35 | 0.02835 | 0.00002835 | 1 | 0.0625 | 0.004464 | 0.00003125 | 0.0000279 | 141.7 |
| lb | 453,592 | 453.6 | 0.4536 | 0.0004536 | 16 | 1 | 0.07143 | 0.0005 | 0.0004464 | 2,268 |
| st | 6,350,293 | 6,350 | 6.35 | 0.00635 | 224 | 14 | 1 | 0.007 | 0.00625 | 31,751 |
| ton | 907,184,740 | 907,185 | 907.2 | 0.9072 | 32,000 | 2,000 | 142.9 | 1 | 0.8929 | 4,535,924 |
| long ton | 1,016,046,909 | 1,016,047 | 1,016 | 1.016 | 35,840 | 2,240 | 160 | 1.12 | 1 | 5,080,235 |
| ct | 200 | 0.2 | 0.0002 | 2 × 10-7 | 0.007055 | 0.0004409 | 0.00003149 | 2.205 × 10-7 | 1.968 × 10-7 | 1 |
Weight units explained
- Milligram (mg)
- A milligram is one thousandth of a gram. It is the usual unit for medicine doses and vitamins.
- Gram (g)
- A gram is one thousandth of a kilogram, about the weight of a paperclip. It is the standard metric unit for food and ingredients.
- Kilogram (kg)
- The kilogram is the base unit of mass in the SI system. It is used for body weight, groceries and parcels in most of the world.
- Metric ton (tonne) (t)
- A metric ton, or tonne, equals 1,000 kilograms. It is used for vehicles, cargo and agricultural yields.
- Ounce (oz)
- An avoirdupois ounce is 1/16 of a pound, or about 28.35 grams. It is used for food, postage and small packages in the US and UK.
- Pound (lb)
- The pound is exactly 0.45359237 kilograms. It is the everyday unit for body weight and groceries in the United States.
- Stone (st)
- A stone is 14 pounds, or about 6.35 kilograms. It is still used in the UK and Ireland for body weight.
- US ton (short ton) (ton)
- The US or short ton is 2,000 pounds, or about 907.18 kilograms. It is smaller than the metric tonne and the British long ton.
- Long ton (long ton)
- The long ton (also called imperial ton) is 2,240 pounds, or about 1,016 kilograms. It is used in the UK for ship displacement.
- Carat (ct)
- A carat is exactly 200 milligrams (0.2 grams) and is the standard unit for the weight of diamonds and other gemstones. Do not confuse it with karat, which describes the purity of gold.