Weight Converter
Convert kilograms, pounds, ounces, stones and more.
Mass vs Weight
Strictly, weight is a force (mass Ć gravity) and mass is the quantity of matter. In everyday usage, the two terms are interchangeable because we always weigh things on Earth where g is roughly constant at 9.81 m/sĀ². Kilograms and pounds are technically units of mass; the newton is the official SI unit of force (and thus true weight). On the Moon, your mass is unchanged but your weight is only 16.5% of Earth's; on Jupiter, 254%.
Reference Conversions
| Conversion | Value |
|---|---|
| 1 kilogram | 2.20462 lb |
| 1 pound | 16 oz = 0.45359 kg |
| 1 ounce | 28.35 g |
| 1 stone (UK) | 14 lb = 6.35 kg |
| 1 metric ton (tonne) | 1,000 kg ā 2,205 lb |
| 1 short ton (US) | 2,000 lb ā 907.2 kg |
| 1 long ton (UK) | 2,240 lb ā 1,016 kg |
| 1 carat (gemstones) | 200 mg = 0.2 g |
The Kilogram Got a Modern Definition in 2019
For over a century, the kilogram was defined as the mass of a specific platinum-iridium cylinder kept in a vault in France (the IPK or "Le Grand K"). In 2019, the SI redefinition tied the kilogram to Planck's constant ā a fundamental physical constant ā making it independent of any physical artifact. This was the biggest update to the SI system in over 100 years.