| Milligrams | 1,000,000 mg |
| Grams | 1,000 g |
| Kilograms | 1 kg |
| Tonnes | 0.001 t |
| Ounces | 35.273962 oz |
| Pounds | 2.204623 lb |
| Stone | 0.157473 st |
Common weight conversions
How to use the Weight Converter
- 1Type the weight you want to convert into the Value box.
- 2Choose the unit you are converting from in the From list.
- 3Choose the unit you want in the To list, or press the swap button to reverse them.
- 4Read the converted weight in the highlighted box.
- 5Use the table to see the same value in all seven units.
How the weight conversions work
The international pound is defined as exactly 0.45359237 kilograms. Every imperial unit in this converter follows from that: an ounce is one-sixteenth of a pound (exactly 28.349523125 grams) and a stone is 14 pounds (exactly 6.35029318 kilograms). The metric units step by factors of 1,000: 1,000 mg in a gram, 1,000 g in a kilogram and 1,000 kg in a metric tonne.
The converter turns your value into kilograms and then into the unit you choose, so every result uses these exact definitions. Answers are shown with up to six decimal places, without trailing zeros. Strictly speaking these are units of mass; in everyday language, and on kitchen and bathroom scales, they are called weight. For distances and heights, use the companion length converter.
Converting kilograms, pounds and stone
To convert kilograms to pounds, divide by 0.45359237, or multiply by about 2.20462. A weight of 70 kg is therefore about 154.32 lb. To go from pounds to kilograms, multiply by 0.45359237: 150 lb is about 68.04 kg.
Stone is still widely used for body weight in the UK and Ireland. To convert stone and pounds to kilograms, multiply the stone by 14, add the pounds and multiply the total by 0.45359237. For example, 12 st 5 lb is 173 lb, or about 78.47 kg. Going the other way, 70 kg is about 11.02 stone, which is 11 st 0.32 lb. Our BMI calculator accepts kilograms or pounds directly if you are checking a healthy weight.
Grams and ounces in the kitchen
Recipes from the United States often list ingredients in ounces and pounds, while most other countries use grams. One ounce is about 28.35 grams, so 5 oz of cheese is about 141.75 g, and 250 g of butter is about 8.82 oz. Note that fluid ounces measure volume, not weight, so they only match weight ounces for water and similar liquids.
For a broader overview of when to use each system, see our guide to metric vs imperial units. It covers weight, length, volume and temperature with practical rounding tips.
Learn more
- What Is BMI and What Does Your Number Mean?What Body Mass Index measures, how it is calculated, what the categories mean and why BMI is only one part of the picture.
- Metric vs Imperial Units: A Practical Conversion GuideHow the metric and imperial systems differ, the exact conversion factors worth remembering and quick mental-math shortcuts.
Frequently asked questions
How many pounds are in a kilogram?
One kilogram is about 2.20462 pounds. The exact relationship is defined the other way around: one pound is exactly 0.45359237 kilograms.
How many pounds are in a stone?
There are exactly 14 pounds in a stone, so one stone is about 6.35 kilograms.
What is the difference between a tonne and a ton?
A tonne, or metric ton, is exactly 1,000 kg. A US short ton is 2,000 lb (about 907 kg), and a UK long ton is 2,240 lb (about 1,016 kg). This converter uses the metric tonne.
How many grams are in an ounce?
One avoirdupois ounce, the kind used for food and body weight, is exactly 28.349523125 grams, usually rounded to 28.35 g. Troy ounces, used for precious metals, are heavier at about 31.1 g.
Can I use these values to plan my diet?
Yes. Converting your weight to kilograms is handy for tools that use metric formulas, such as the calorie calculator, although it accepts pounds too.