Weight Converter
Convert between kilograms, pounds, ounces, stones, grams and tonnes.
How to Convert Between Weight Units
Weight conversion is one of the most common unit conversions in everyday life — whether you're comparing grocery prices, following a recipe, tracking fitness goals, or understanding a medical measurement. The metric system uses kilograms and grams as its base units, while the imperial system (used primarily in the United States, United Kingdom, and a handful of other countries) uses pounds, ounces, and stone.
Our weight converter handles eight units instantly: kilograms, grams, milligrams, pounds, ounces, tonnes, stone (UK), and micrograms. Simply enter a value, select your input and output units, and the converted result appears immediately.
Weight Conversion Reference Table
The most frequently needed conversions, pre-calculated for easy reference:
| From | To | Multiply by | Example |
|---|---|---|---|
| Kilograms (kg) | Pounds (lb) | 2.20462 | 70 kg = 154.32 lb |
| Pounds (lb) | Kilograms (kg) | 0.453592 | 150 lb = 68.04 kg |
| Kilograms (kg) | Stone (st) | 0.157473 | 80 kg = 12 st 8 lb |
| Stone (st) | Kilograms (kg) | 6.35029 | 11 st = 69.85 kg |
| Grams (g) | Ounces (oz) | 0.035274 | 250 g = 8.82 oz |
| Ounces (oz) | Grams (g) | 28.3495 | 16 oz = 453.59 g |
| Pounds (lb) | Ounces (oz) | 16 | 2.5 lb = 40 oz |
| Tonnes (t) | Kilograms (kg) | 1000 | 1 t = 1,000 kg |
Kilograms vs Pounds — The Key Difference
Kilograms (kg) are the standard unit of mass in the International System of Units (SI) and are used by the vast majority of the world. One kilogram equals approximately 2.205 pounds. Pounds (lb) are used primarily in the United States and, to a lesser extent, the United Kingdom for body weight. For body weight specifically, the UK also commonly uses stone — one stone equals 14 pounds or approximately 6.35 kilograms.
Understanding Stone (UK)
Stone is a unit of weight used almost exclusively in the United Kingdom and Ireland for expressing human body weight. One stone equals exactly 14 pounds or 6.35029 kilograms. A person weighing 75 kg would be approximately 11 stone 11 pounds (written 11 st 11 lb). While the NHS in the UK officially uses kilograms, many British people still think of their weight in stone and pounds.
For rough mental conversions: 1 kg ≈ 2.2 lb, 1 lb ≈ 0.45 kg, 1 stone ≈ 6.35 kg. To go from kg to lb in your head, double the kg value and add 10% — so 70 kg × 2 = 140, plus 10% = 154 lb (actual: 154.3 lb).
Common Weight Conversions in Context
| Context | Metric | Imperial |
|---|---|---|
| Average adult body weight | 70 kg | 154 lb / 11 st |
| Newborn baby | 3.5 kg | 7 lb 11 oz |
| 1 bag of flour | 1 kg | 2 lb 3 oz |
| 1 can of soda | 330 g | 11.6 oz |
| Small car | 1,200 kg | 2,646 lb |
Frequently Asked Questions
How many pounds are in a kilogram?
One kilogram equals exactly 2.20462 pounds. For everyday use, 2.2 lb per kg is a close enough approximation. So 5 kg ≈ 11 lb, 10 kg ≈ 22 lb, and 100 kg ≈ 220 lb.
How do I convert kg to stone and pounds?
First multiply the kg value by 2.20462 to get total pounds. Then divide the total pounds by 14 — the whole number is the stone value. Multiply the remaining decimal by 14 to get the leftover pounds. Example: 76 kg × 2.20462 = 167.55 lb. 167.55 ÷ 14 = 11 stone remainder 13.55 lb, so 76 kg ≈ 11 st 14 lb (or roughly 12 stone).
What is the difference between mass and weight?
Technically, mass is the amount of matter in an object (measured in kilograms), while weight is the force exerted by gravity on that mass (measured in newtons). In everyday language, however, "weight" and "mass" are used interchangeably — when you step on a scale, you're measuring your mass, but we call the reading your "weight." This converter works with mass units as used in everyday contexts.
How many ounces are in a pound?
There are exactly 16 ounces (oz) in one pound (lb). This is the avoirdupois pound used for everyday weight measurement. Note that there is also a troy pound used for precious metals, which contains 12 troy ounces — but this is rarely encountered outside of jewellery and bullion contexts.
How do I convert grams to ounces for cooking?
Multiply the gram value by 0.035274. For quick kitchen conversions: 100 g ≈ 3.5 oz, 250 g ≈ 8.8 oz, 500 g ≈ 17.6 oz. A standard US cup of water is 236 g (8.33 oz). Most professional bakers prefer grams because they are more precise than volume measurements like cups.
Is a pound heavier than 500 grams?
No — one pound equals 453.59 grams, so a pound is slightly less than 500 grams. Half a kilogram (500 g) is about 10% heavier than one pound. This distinction matters in cooking when recipes switch between metric and imperial — "a pound of butter" and "500g of butter" are close but not identical.