How many pounds are in a kilogram?
The international avoirdupois pound (lb, plural lbs) has been defined since 1959 as exactly 0.45359237 kilograms. So:
lbs = kg × 2.20462 · kg = lbs × 0.45359237
The abbreviation lb comes from the Latin libra. A pound has 16 ounces (oz) of about 28.35 grams each.
In the United Kingdom and Ireland body weight is often given in stone: 1 stone is 14 pounds, or 6.35 kg. Someone who weighs "11 stone 4" weighs 11 stone and 4 pounds, which is 158 lb or 71.7 kg.
Examples
- 70 kg to lbs: 70 × 2.20462 = 154.32 lbs, or about 11 stone.
- 150 lbs to kg: 150 × 0.45359 = 68.04 kg.
- 11 stone 4 to kg: (11 × 14 + 4) × 0.45359 = 158 × 0.45359 = 71.67 kg.
- A 50 lb suitcase: many US airlines set 50 lb as the checked-bag limit. That is 22.7 kg, slightly less than the 23 kg European airlines often quote.
Conversion chart: kg to lbs
| Kilograms | Pounds (lbs) | Stone |
|---|---|---|
| 50 kg | 110.2 lbs | 7 st 12.2 lb |
| 60 kg | 132.3 lbs | 9 st 6.3 lb |
| 70 kg | 154.3 lbs | 11 st 0.3 lb |
| 80 kg | 176.4 lbs | 12 st 8.4 lb |
| 90 kg | 198.4 lbs | 14 st 2.4 lb |
| 100 kg | 220.5 lbs | 15 st 10.5 lb |
Mental math shortcuts
- kg to lbs: double it and add 10%. 70 kg → 140 + 14 = 154 lbs (exact: 154.3).
- lbs to kg: halve it and subtract 10%. 200 lbs → 100 − 10 = 90 kg (exact: 90.7).
Both shortcuts are accurate to about 1%.
Pounds in daily life
- Gym equipment: plates and dumbbells from American brands are marked in lbs. A 45 lb plate is 20.4 kg; a standard Olympic barbell of 20 kg is about 44 lb.
- Recipes: American and older British recipes use pounds and ounces. "1 lb butter" is about 454 g. Note that in the Netherlands and Germany a "pound" at the market is 500 g.
- Travel: airline baggage limits in the US and UK are given in pounds.
- Health: doctors in the US record weight in pounds, while BMI formulas work in kilograms. Use the BMI calculator with either unit system.
To convert lengths, use cm to inches; for other units, see the unit converter.
A short history
The pound has had many local versions over the centuries, from the Roman libra to the Tower pound and the troy pound still used for precious metals (373.2 g). The avoirdupois pound used for everyday goods became the standard in English-speaking countries. In 1959 the US, UK, Canada, Australia, New Zealand and South Africa agreed to define it via the kilogram, which is why the conversion factor is exact.
Where you meet pounds and kilograms
Pounds remain the everyday unit for body weight in the United States, and the UK often uses stones and pounds. Gym weights and dumbbells are frequently labelled in pounds, as are boxers and MMA fighters at weigh-ins. Airlines often state baggage limits in both: 50 lb is about 22.7 kg, slightly less than the common 23 kg limit, while 23 kg is about 50.7 lb. Recipes from the US list butter, meat and flour in pounds and ounces, whereas European recipes use grams. Medical dosing, science and almost all international trade use kilograms. If you want to put your weight in context, try the BMI calculator as well.
Frequently asked questions
How many kg is 1 lb?
Exactly 0.45359237 kg, so about 454 grams.
How many lbs is 1 kg?
About 2.2046 lbs. Ten kilograms is a little over 22 lbs.
What is the difference between lb and lbs?
None. Lb is the official abbreviation; lbs is commonly used as the plural. Both mean pounds.
How many kg is a stone?
One stone is 14 pounds, or 6.35 kg. It is mainly used for body weight in the UK and Ireland.
How do I convert stones and pounds to kg?
Multiply the stones by 14, add the pounds, then multiply by 0.4536. 12 st 6 lb = 174 lb = 78.9 kg.
How heavy is an ounce?
An ounce (oz) is about 28.35 grams, and 16 ounces make a pound. A fluid ounce is a volume, not a weight.
Last reviewed: 2026-10-06. Results are estimates for information only.