Weight Converter
Convert between kg, lbs, stone, grams and ounces instantly.
Last updated: April 2026
Convert from:
Common weights:
| Unit | Amount |
|---|---|
| Kilograms | — kg |
| Pounds | — lbs |
| Stone | — st |
| Grams | — g |
| Ounces | — oz |
Common conversions
| Kilograms | Pounds | Stone |
|---|---|---|
| 70 kg | 154.3 lbs | 11 st 0.3 lbs |
| 75 kg | 165.3 lbs | 11 st 11.3 lbs |
| 80 kg | 176.4 lbs | 12 st 8.4 lbs |
| 90 kg | 198.4 lbs | 14 st 2.4 lbs |
| 100 kg | 220.5 lbs | 15 st 10.5 lbs |
Weight is measured differently depending on where you are in the world. The metric system uses kilograms and grams; the US uses pounds and ounces; the UK and Ireland traditionally use stone for body weight. These systems don't share a common base, so converting between them requires a fixed ratio — there's no rounding shortcut that works cleanly across all five units.
Reference weights
Airline baggage limits
| Baggage type | kg | lbs |
|---|---|---|
| Hand luggage (typical) | 7–10 kg | 15–22 lbs |
| Economy checked baggage | 20–23 kg | 44–51 lbs |
| Business class checked baggage | 32 kg | 71 lbs |
Everyday objects
| Object | kg | lbs |
|---|---|---|
| 1 litre of water | 1 kg | 2.2 lbs |
| Bag of flour | 1.5 kg | 3.3 lbs |
| Carry-on suitcase (empty) | 3–4 kg | 6.6–8.8 lbs |
| Average adult female | 65 kg | 143 lbs |
| Average adult male | 80 kg | 176 lbs |
When do you need this?
- Checking your body weight when a doctor's form asks in a different unit than your bathroom scale shows
- Following a US recipe that lists ingredient weights in ounces or pounds
- Booking a flight and calculating whether your checked bag meets the airline's allowance — carriers use kg or lbs depending on their origin country
- Reading a UK fitness article that gives body weight in stone when your scale shows kilograms
- Comparing supplement or protein powder serving sizes across brands that use different units
- Shipping a parcel internationally where the courier requires weight in a specific unit
Quick reference
- 1 kg = 2.20462 lbs (approx. 2.2 lbs)
- 1 lb = 0.453592 kg (approx. 0.454 kg)
- 1 stone = 14 lbs = 6.35029 kg (approx. 6.35 kg)
- 1 oz = 28.3495 g (approx. 28.35 g)
- 1 lb = 16 oz = 453.592 g (approx. 454 g)
- 1 kg = 1000 g = 35.274 oz
Understanding the units
Kilograms (kg)
The kilogram is the base unit of mass in the International System of Units (SI) and is used by most countries worldwide. It's the standard for body weight, food packaging, and scientific measurement. One kilogram is exactly 1000 grams.
Pounds (lbs)
The pound is the primary unit of weight in the United States and is still widely used in the UK alongside metric. It originates from the Roman libra, which is why its abbreviation is "lb." One pound equals 16 ounces, or approximately 453.6 grams. Body weight in the US is almost always expressed in pounds.
Stone (st)
The stone is used almost exclusively in the United Kingdom and Ireland for measuring body weight — you'll rarely see it applied to anything else. One stone equals exactly 14 pounds, or about 6.35 kg. Most British bathroom scales display weight in stone and pounds combined (e.g. "11 st 4 lbs").
Grams (g)
Grams are the standard unit for small weights — recipe ingredients, postal items, nutrition labels, and medication doses. One gram is one-thousandth of a kilogram. For cooking, grams are more precise than volume measurements like cups or tablespoons.
Ounces (oz)
Ounces are used in the US for food portions and small package weights. One ounce equals approximately 28.35 grams, and 16 ounces make one pound. This is the avoirdupois ounce — not the fluid ounce, which measures volume and is a different quantity entirely.
Common mistakes
- Confusing fluid ounces (volume) with ounces (weight) — they are not interchangeable, even for water
- Assuming stone is used globally — outside the UK and Ireland, most people won't know their weight in stone
- Rounding 1 kg to 2 lbs instead of 2.2 lbs — across 10 kg that error compounds to 2 lbs off
- Forgetting that stone is always paired with pounds — "12 st 6 lbs" is not the same as "12.6 stone"
- Using 500 g as a rough pound equivalent — the correct value is ~453.6 g, which matters in precise recipes
Which should you use?
- For body weight in most countries: kilograms — it's what doctors and health apps use internationally.
- For body weight in the US: pounds — scales, BMI calculators, and health records default to lbs.
- For body weight in the UK/Ireland: stone and pounds — still the most common way people describe themselves colloquially.
- For cooking and recipes: grams for precision; ounces if following a US recipe.
- For luggage and shipping: check the carrier — airlines and couriers may use either kg or lbs depending on their origin country.
Frequently asked questions
How many kg is 1 stone?
One stone is equal to 6.35029 kilograms, or exactly 14 pounds. Stone is used almost exclusively in the UK and Ireland for body weight. If someone says they weigh "11 stone", that's 69.85 kg or about 154 lbs.
How many pounds is 1 kg?
One kilogram equals approximately 2.20462 pounds. For a quick mental estimate, multiplying kg by 2.2 is accurate enough for most purposes. So 70 kg ≈ 154 lbs, and 80 kg ≈ 176 lbs.
What is the airline baggage weight limit in kg?
Most airlines allow 7–10 kg for hand luggage and 20–23 kg for economy checked baggage. Business class checked allowances are typically 32 kg. Always confirm with your specific carrier before travelling — limits vary by route and ticket type.
How many grams in a pound?
One pound equals exactly 453.592 grams. The rounded figure of 454 g is close enough for most cooking. For precision baking or pharmaceutical work, use the full value.
What countries use stone for weight?
Stone is used almost exclusively in the United Kingdom and Ireland, and only for body weight — not for objects, packages, or scientific contexts. Most other English-speaking countries, including the US, Canada, and Australia, do not use stone.
Is 1 oz the same as a fluid ounce?
No. A standard ounce (oz) measures mass — approximately 28.35 grams. A fluid ounce (fl oz) measures volume — approximately 29.57 ml in the US system. They only roughly coincide for water. Don't substitute one for the other in recipes.
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- Cooking converter — convert cups, tablespoons, grams and ml for recipes
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