Weight Converter — Convert kg, lbs, stones, ounces, and More
Weight conversion is needed in everyday situations: understanding your weight in different units, checking luggage allowances, reading recipes from another country, or following a nutrition plan. The UK and US use imperial units (stones and pounds, pounds and ounces) alongside metric (kilograms, grams), creating frequent conversion needs. The free weight converter on PublicSoftTools converts between all common weight units instantly.
How to Use the Weight Converter
- Open the weight converter.
- Select the unit you are converting from (e.g., kilograms).
- Enter the weight value.
- The converter instantly shows the equivalent in all other weight units.
- Click any result to copy it to your clipboard.
Weight Conversion Reference Table
| Unit | = kg | = lbs | = stones | = oz | Notes |
|---|---|---|---|---|---|
| Kilogram (kg) | 1 | 2.20462 | 0.157473 st | 35.274 oz | SI base unit of mass; standard for most countries and science |
| Pound (lb) | 0.453592 | 1 | 0.0714286 st | 16 oz | US and UK common unit; 1 lb = 16 oz exactly |
| Stone (st) | 6.35029 | 14 | 1 | 224 oz | UK/Ireland only; not used elsewhere; 1 stone = 14 lbs exactly |
| Ounce (oz) | 0.0283495 | 0.0625 | 0.00446429 st | 1 | 16 oz = 1 lb; used in US cooking and nutrition labels |
| Gram (g) | 0.001 | 0.00220462 | 0.000157473 st | 0.035274 oz | 1000 g = 1 kg; used in recipes, nutrition, postal weights |
| Metric tonne (t) | 1000 | 2,204.62 | 157.473 st | 35,274 oz | For large masses; 1 metric tonne = 1000 kg = 2,204.62 lbs |
| US short ton | 907.185 | 2000 | 142.857 st | 32,000 oz | US industrial weight; 2,000 lbs; different from metric tonne (2,204 lbs) |
| UK long ton | 1016.05 | 2240 | 160 st | 35,840 oz | Imperial; 2,240 lbs; different from US short ton and metric tonne |
Common Reference Weights
| Item | Weight (metric) | Weight (imperial) | Notes |
|---|---|---|---|
| A slice of bread | ~30 g | ~1.06 oz | Varies by bread type and slice thickness |
| A can of soup (standard UK) | 400 g | 14.1 oz (0.88 lb) | |
| Average UK adult (male) | ~84 kg | ~13 st 3 lb / 185 lb | NHS Health Survey for England 2022 average |
| Average UK adult (female) | ~70 kg | ~11 st 0 lb / 154 lb | |
| Newborn baby | ~3.5 kg | ~7 lb 11 oz | UK average birth weight for full-term singleton |
| Bag of sugar (UK) | 1 kg | 2.2 lb | Standard UK supermarket bag size |
| Heavyweight boxing limit | No upper limit (above 200 lb / 90.7 kg) | No upper limit | WBC, WBA, IBF unified upper limit |
| London Heathrow checked baggage limit | 23 kg | 50.7 lb | Standard economy class baggage allowance on most airlines |
Converting Stones and Pounds
The UK traditionally expresses body weight in stones and pounds — a unit combination not used anywhere else in the world. One stone = exactly 14 pounds.
To convert kilograms to stones and pounds:
- Multiply kg by 2.20462 to get total pounds
- Divide total pounds by 14 to get stones (take the floor for whole stones)
- Remaining pounds = total pounds − (stones × 14)
Example: 70 kg → 70 × 2.20462 = 154.32 lb → 154.32 / 14 = 11.02 stones → 11 stones and (154.32 − 154) = 0.32 lb. But 0.32 of a pound is not commonly used — round to the nearest pound: 11 stone 0 lb ≈ 70 kg.
More precisely: 70 kg = 11 st 0.3 lb ≈ 11 stone flat.
UK vs. US Weight Units
The UK uses both metric and imperial units in different contexts:
- Body weight: Often expressed in stones and pounds (e.g., 11st 4lb) or kilograms. NHS increasingly uses kilograms; many people still think in stones.
- Food and recipes: UK recipes use grams and kilograms. US recipes use ounces, pounds, and cups.
- Postal/parcel weight: Kilograms (g, kg) used across the UK and EU.
- Industrial/freight: Tonnes (metric) in the UK; short tons in the US.
The US primarily uses pounds and ounces for everyday weight. The US does not use stones. Food labels use ounces and pounds; scientific and pharmaceutical weights use grams and kilograms.
Mass vs. Weight
In everyday language, "weight" usually refers to mass — how much matter something contains, measured in kilograms or pounds. Scientifically, weight is the gravitational force on an object (measured in newtons), while mass is the amount of matter (measured in kg).
On Earth at standard gravity (9.81 m/s²): weight in newtons = mass in kg × 9.81. A 70 kg person weighs 70 × 9.81 = 686.7 N. But in everyday usage — bathroom scales, luggage limits, food labels — "weight" means mass in kg or lbs.
Scales technically measure gravitational force and convert to mass assuming you are on Earth's surface. On the Moon (g = 1.62 m/s²), the same scale would read approximately 1/6 of your Earth mass — the scale's calibration is Earth-specific.
Cooking Weight Conversions
Converting between US and UK recipes often requires weight conversions. Common cooking weights:
- 1 cup of flour ≈ 120–130 g (varies with type and how it's scooped)
- 1 cup of sugar ≈ 200 g
- 1 cup of butter ≈ 227 g (2 sticks US = 225 g)
- 1 tablespoon of butter ≈ 14 g (½ oz)
- 1 oz ≈ 28.35 g (28 g is the usual baking approximation)
Professional baking uses weights rather than volumes for precision — 125 g of flour is consistent regardless of how it's measured, while a "cup" of flour varies by up to 20% depending on technique.
Common Questions
How many pounds in a stone?
There are exactly 14 pounds in 1 stone. This is a fixed conversion: 1 st = 14 lb exactly. The stone is a traditional British unit used primarily for body weight — it is not an SI unit and is not officially recognised in the metric system, but remains widely used in the UK and Ireland.
What is the difference between a metric tonne and a US ton?
A metric tonne (t) = 1,000 kg = 2,204.62 lb. A US short ton = 2,000 lb = 907.18 kg. A UK long ton = 2,240 lb = 1,016.05 kg. The three "tonnes"/"tons" have different values. When a weight is given in "tons" without specification, context determines which is meant — in science and international trade, "tonne" (with the 'e') means the metric tonne.
How do I convert grams to ounces for recipes?
1 gram = 0.035274 ounces, or equivalently 1 ounce = 28.3495 grams (≈ 28 g for cooking purposes). Quick conversions: 100 g ≈ 3.5 oz; 200 g ≈ 7 oz; 500 g ≈ 17.6 oz (just over 1 lb); 1 kg ≈ 2.2 lb. The weight converter handles any gram or ounce value instantly.
Convert Any Weight
Enter any weight in kg, lbs, stones, ounces, or grams to instantly see the equivalent in all other units.
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