Weight Converter
Convert between milligrams, grams, kilograms, tonnes, ounces, pounds and stones.
The weight converter converts between metric and imperial units of mass. It is handy for cooking, shipping, luggage limits, gym weights and reading product labels from other countries.
How to use the converter
- Enter the weight you want to convert.
- Select the from and to units.
- See the result and a table of the same weight in every other unit.
- Use the swaps for reverse conversions.
How the conversion works
Result = value in kilograms ÷ factor of the target unit
Worked example
70 kilograms to pounds
70 kg ÷ 0.45359237 = 154.32 pounds
In stones that is about 11 st 0.3 lb, and 70 kg is 70,000 grams.
Popular conversions
Jump straight to a single conversion, or use the converter above for any pair.
Who should use this weight converter
- Cooks following recipes from other countries, where ingredients are listed in ounces or pounds.
- Travellers checking airline baggage limits, usually quoted in kilograms but sometimes in pounds.
- Anyone at the gym comparing body weight or plates against a programme written in pounds.
- Shoppers reading nutrition labels or shipping documents from abroad where the mass is in unfamiliar units.
Common mistakes to avoid
- Confusing mass with weight. A kilogram measures how much matter an object contains, while weight is a force that changes with gravity. Mass stays the same on the Moon; weight does not.
- Mixing weight ounces with fluid ounces. A fluid ounce measures volume and only roughly equals an ounce of water. They are different quantities.
- Assuming all tons are the same. A metric tonne is 1,000 kg, a US short ton is 907.18 kg and a UK long ton is 1,016.05 kg. In shipping, that difference matters.
- Using 2.2 pounds per kilogram for precise work. The exact factor is 2.20462. At 100 kg the shortcut is off by nearly half a kilogram.
- Forgetting that stones are still used for body weight. In the UK and Ireland, 70 kg is often quoted as about 11 stone, with 14 pounds to a stone.
Mass, weight and why the distinction matters
Strictly speaking, kilograms measure mass and pounds measure force, but in everyday use both are treated as measures of how heavy something is. The confusion only becomes practical in a few places: science homework, engineering, and scales calibrated in different countries.
Where it does matter in daily life is cooking. Recipes use mass because mass does not change with location or temperature, whereas volume measures such as cups vary with how tightly an ingredient is packed. A cup of flour can weigh anywhere between 120 and 150 grams depending on the method. That is why a kitchen scale is more reliable than a measuring cup, and why converting a recipe from ounces to grams is worth doing precisely.
Weight units explained
- Kilogram
- The SI base unit of mass, and the standard for body weight almost everywhere.
- Pound
- Exactly 0.45359237 kilograms. Commonly shortened to lb.
- Ounce
- One sixteenth of a pound, or about 28.35 grams. It is a unit of mass, not volume.
- Stone
- Fourteen pounds, still used for body weight in the UK and Ireland.
- Metric tonne
- 1,000 kilograms. It differs from the US short ton and the UK long ton.
Conversions people look up most
A few anchors make everyday conversions quick. One kilogram is 2.20462 pounds, so 5 kg is about 11 pounds, 10 kg about 22 pounds and 50 kg about 110.2 pounds. Going the other way, one pound is 0.4536 kilograms, which means 100 pounds is about 45.4 kilograms.
Luggage is where this comes up most often. A 23 kg cabin-plus-checked allowance is 50.7 pounds, and a 7 kg cabin bag is 15.4 pounds. Body weight is the other common case: 70 kg is 154.3 pounds, or roughly 11 stone. For anything precise, use the exact factor rather than the rounded 2.2, which drifts by nearly half a kilogram at 100 kg.
Frequently asked questions
How many pounds are in a kilogram?
One kilogram equals about 2.20462 pounds. To convert kilograms to pounds, multiply by 2.20462; to go the other way, divide by the same number.
Is a metric tonne the same as a ton?
A metric tonne is 1,000 kilograms, while a US short ton is 907.18 kg and a UK long ton is 1,016.05 kg. The three are close but not identical.
What is a stone?
A stone is a British unit equal to 14 pounds, still commonly used for body weight in the UK and Ireland. Someone weighing 70 kg is about 11 stone.