Weight Converter
Convert units of weight and mass — kilograms, grams, pounds, ounces, stones, tons and more.
1 kg = 2.2046226 lb
Popular Weight Conversions
- Microgram to Pound
- Milligram to Pound
- Gram to Pound
- Kilogram to Pound
- Metric Ton to Pound
- US Ton to Pound
- Imperial Ton to Pound
- Ounce to Pound
- Stone to Pound
- Carat to Pound
- Grain to Pound
- Slug to Pound
- Kilogram to Microgram
- Kilogram to Milligram
- Kilogram to Gram
- Kilogram to Metric Ton
- Kilogram to US Ton
- Kilogram to Imperial Ton
- Kilogram to Ounce
- Kilogram to Stone
- Kilogram to Carat
- Kilogram to Grain
- Kilogram to Slug
About weight units
Weight — more precisely mass in everyday usage — measures how much matter an object contains. The kilogram is the SI base unit and is used worldwide in science, medicine, and commerce. In the United States, pounds and ounces remain the everyday standard for groceries, body weight, and postal rates. The UK occupies a middle ground: supermarkets label in grams, but many people still describe their body weight in stones and pounds, where one stone equals exactly 14 pounds. At the industrial scale, three different 'tons' coexist: the metric ton (1,000 kg), the US short ton (about 907 kg), and the imperial long ton (about 1,016 kg).
History & origin
The kilogram was introduced during the French Revolution alongside the entire metric system. Until 2019 it was literally defined by the mass of a platinum-iridium cylinder kept in Sèvres, France — the only SI base unit still anchored to a physical artifact. That changed in May 2019, when the kilogram was redefined in terms of Planck's constant, making it reproducible without reference to any single object. The pound traces back through Old English and Old French to the Roman libra pondo ('a pound by weight'), which is also why the symbol is 'lb'.
Tips
Mass and weight are not the same thing — mass is the amount of matter (kilograms), weight is the gravitational force on that mass (newtons) — but converters treat them interchangeably at standard Earth gravity, which is fine for everyday use. The trickiest conversion is between the three tons: if a shipping spec says 'ton' without a qualifier, ask whether it means short, long, or metric before you order material.
Common questions
- How many pounds are in a kilogram?
- One kilogram is defined as exactly 2.204622… pounds, which comes from the exact definition 1 lb = 0.45359237 kg. For quick mental math, 1 kg ≈ 2.2 lb works well; for body weight comparisons, a 70 kg person weighs about 154 lb or 11 stone.
- What is a stone, and who uses it?
- A stone is exactly 14 pounds (≈ 6.35 kg). It is used almost exclusively in the United Kingdom and Ireland for expressing body weight. It rarely appears in scientific or commercial contexts anywhere.
- What is the difference between a metric ton, a US ton, and an imperial ton?
- A metric ton (tonne) is exactly 1,000 kg. A US short ton is 2,000 lb ≈ 907 kg. An imperial long ton is 2,240 lb ≈ 1,016 kg. When a document simply says 'ton,' you need context to know which one is meant — the three differ by up to 12%.