Convert between kilograms, pounds, ounces, grams, stones, metric tons, and short tons instantly. Accurate weight conversions for body weight, cooking, shipping, and more.
The most commonly needed weight conversions at a glance
Enter a weight in any unit and get instant results in kilograms, pounds, ounces, grams, stones, and tons.
Open Unit Converter →Our weight converter supports all major units used globally:
Metric: milligrams (mg), grams (g), kilograms (kg), metric tons / tonnes (t)
Imperial/US: ounces (oz), pounds (lb), short tons (US ton)
British: stones (st), long tons
The base SI unit for weight (technically mass) is the kilogram. All conversions chain through kilograms. The fundamental anchor: 1 pound = 0.45359237 kg exactly (defined internationally since 1959).
Medical professionals worldwide use kilograms for body weight because nearly all drug dosing, nutritional guidelines, and clinical measurements are defined in metric units. Drug dosages are calculated as mg/kg — if your weight is only in pounds, the calculation requires conversion first, introducing potential for error.
Common body weight conversions:
100 lbs = 45.4 kg | 120 lbs = 54.4 kg | 140 lbs = 63.5 kg | 160 lbs = 72.6 kg
180 lbs = 81.6 kg | 200 lbs = 90.7 kg | 220 lbs = 99.8 kg | 250 lbs = 113.4 kg
Professional recipes, especially from European sources, use grams and kilograms. Home baking in the US typically uses cups and ounces. Weight measurements are generally more accurate than volume for dry ingredients — a "cup of flour" can vary by up to 30% depending on how it's scooped, while a gram measurement is exact.
Common cooking weight conversions:
1 oz = 28.35 g | 4 oz = 113.4 g | 8 oz = 226.8 g (half pound)
1 lb = 453.6 g | 500 g = 17.64 oz | 1 kg = 35.27 oz = 2.205 lbs
Butter: US recipes often call for cups or tablespoons (1 cup butter = 227g). European recipes use grams. 1 stick of US butter = 4 oz = 113g.
Gyms in the US primarily label weights in pounds, while gyms in most other countries use kilograms. This creates confusion when following international workout programs or moving between countries:
45 lb plate = 20.4 kg | 35 lb plate = 15.9 kg | 25 lb plate = 11.3 kg | 10 lb plate = 4.5 kg
20 kg plate = 44.1 lbs | 15 kg plate = 33.1 lbs | 10 kg plate = 22.0 lbs
A common benchmark in powerlifting — "benching your bodyweight" — converts the same: if you weigh 80 kg (176 lbs) and bench 80 kg, you've benched your bodyweight regardless of unit.
The stone is a unit of weight used almost exclusively in the UK and Ireland for expressing body weight. 1 stone = 14 pounds = 6.35 kilograms. It's not part of the metric or standard imperial systems but persists in British culture for body weight discussions.
Understanding British weight descriptions: "12 stone" = 168 lbs = 76.2 kg. "14 stone 7" means 14 stones and 7 pounds = 14×14 + 7 = 203 lbs = 92.1 kg. The stone has no legal status in EU commerce but remains in everyday UK use.
International shipping uses kilograms for weight calculations. US domestic shipping often uses pounds. Airlines typically set baggage limits in kilograms (23 kg = 50.7 lbs per checked bag on most international flights). US domestic carriers often list limits in pounds (50 lbs = 22.7 kg).
1 kg = 2.20462 lbs. Multiply kg by 2.205 for pounds. Divide lbs by 2.205 for kg. 70 kg = 154.3 lbs. 150 lbs = 68.0 kg.
1 oz = 28.3495 grams. Multiply oz by 28.35 for grams. 8 oz = 226.8 g. 100 g = 3.527 oz. 500 g = 17.64 oz.
1 stone = 14 lbs = 6.35 kg. Used in UK/Ireland for body weight. "11 stone 4" = (11×14)+4 = 158 lbs = 71.7 kg. Multiply stone by 6.35 for kg, or by 14 for lbs.
Metric ton (tonne) = 1,000 kg = 2,204.6 lbs. US short ton = 2,000 lbs = 907.2 kg. The metric ton is about 10% heavier. International trade uses metric tonnes; US domestic often uses short tons.