Weight Converter
Quick Conversions
Related Converters
Weight and Mass Units
Mass vs Weight
Technically, mass and weight are different. Mass is the amount of matter in an object (measured in kilograms), while weight is the force of gravity on that mass (measured in newtons). In everyday use, we use them interchangeably.
Metric Units
Milligram (mg)
One thousandth of a gram. Used for medication dosages, vitamins, and small quantities.
Gram (g)
Base metric unit for small weights. A paperclip weighs about 1 gram. Used for food, jewelry, etc.
Kilogram (kg)
1,000 grams. Standard unit for body weight in most countries. A liter of water weighs about 1 kg.
Metric Tonne (t)
1,000 kilograms. Used for heavy loads, vehicles, cargo. Slightly more than a US ton.
Imperial Units
Ounce (oz)
1/16 of a pound. Used for food packages, baby weights. About 28.35 grams.
Pound (lb)
16 ounces. Standard unit for body weight in US. About 0.45 kilograms.
Stone (st)
14 pounds. Used for body weight in UK and Ireland. About 6.35 kilograms.
US Ton
2,000 pounds (short ton). Used in United States for heavy items. About 907 kg.
Conversion Formulas
pounds = kg × 2.205
kg = pounds × 0.4536
ounces = grams × 0.03527
grams = ounces × 28.35
stones = kg × 0.1575
Troy vs Avoirdupois
Precious metals (gold, silver) use Troy ounces, which are different from regular (avoirdupois) ounces. 1 Troy ounce = 31.1 grams, while 1 regular ounce = 28.35 grams.
Frequently Asked Questions
How do I convert pounds to kilograms?
Multiply pounds by 0.4536 to get kilograms. For example, 150 pounds × 0.4536 = 68.04 kg. For a quick estimate, divide pounds by 2.2. To convert kg to pounds, multiply by 2.205.
How many grams are in an ounce?
One avoirdupois ounce (regular ounce) equals 28.35 grams. To convert ounces to grams, multiply by 28.35. To convert grams to ounces, divide by 28.35. Note: A troy ounce (for precious metals) is different at 31.1 grams.
What is a stone and how do I convert it?
A stone is a British unit equal to 14 pounds or about 6.35 kg. It's commonly used for body weight in the UK and Ireland. To convert stone to pounds, multiply by 14. To convert stone to kg, multiply by 6.35.
What's the difference between mass and weight?
Mass is the amount of matter in an object (measured in kg), while weight is the gravitational force on that mass (measured in newtons). Your mass stays constant everywhere, but your weight changes with gravity. On the Moon, you'd weigh 1/6 as much but have the same mass.