Weight (strictly, mass) shows up in recipes, shipping labels, gym plates and gold prices, each in its own units. The pound is defined as exactly 0.45359237 kg, so conversions between metric and U.S. or imperial weights are exact.
How to use the Weight Converter
- Pick the unit you are starting from in the From menu and type your value.
- Pick the unit you want in the To menu. The heading changes to match – for example “Kilograms to Grams Converter”.
- The most common mass units are shown below at the same time, so you can compare them at a glance.
- Type into any result to convert backwards, then use Copy results – the copied text starts with the heading for your chosen units.
Results update as you type. Everything is calculated in your browser.
How it works
Every mass unit is defined by an exact factor relative to the kilogram (the base unit). The calculator first turns the value you type into kilograms, then turns that into the unit you picked in the “To” menu and into each of the common units below it. This two-step method means any unit can be converted to any other – 19 units are available in each menu – and you can type into any field, including a result, to work in the other direction. Changing a unit menu keeps the quantity the same and just re-expresses it, and the page heading and copied results follow your choice.
How to convert mass units
- Choose the unit you have in the From menu and type the value, for example 1 kg.
- Choose the unit you want in the To menu, for example grams. The page heading changes to “Kilograms to Grams Converter”.
- The calculator multiplies by the kilogram factor of the “from” unit and divides by the factor of the “to” unit: 1 kg × 1 ÷ 0.001 = 1,000 g.
1 kilogram in common units
| Unit | Value |
|---|---|
| Grams (g) | 1,000 |
| Milligrams (mg) | 1,000,000 |
| Tonnes (t) | 0.001 |
| Pounds (lb) | 2.2046226 |
| Ounces (oz) | 35.273962 |
| Stone (st) | 0.15747304 |
| Short tons (US ton) | 0.0011023113 |
| Troy ounces (ozt) | 32.150747 |
Kilograms conversion table
| Kilograms | g | mg | t | lb |
|---|---|---|---|---|
| 0.1 | 100 | 100,000 | 0.0001 | 0.22046226 |
| 0.5 | 500 | 500,000 | 0.0005 | 1.1023113 |
| 1 | 1,000 | 1,000,000 | 0.001 | 2.2046226 |
| 2 | 2,000 | 2,000,000 | 0.002 | 4.4092452 |
| 5 | 5,000 | 5,000,000 | 0.005 | 11.023113 |
| 10 | 10,000 | 10,000,000 | 0.01 | 22.046226 |
| 20 | 20,000 | 20,000,000 | 0.02 | 44.092452 |
| 50 | 50,000 | 50,000,000 | 0.05 | 110.23113 |
| 70 | 70,000 | 70,000,000 | 0.07 | 154.32358 |
| 100 | 100,000 | 100,000,000 | 0.1 | 220.46226 |
What is a kilogram?
The kilogram is the SI base unit of mass. Since 2019 it has been defined through the Planck constant rather than a platinum-iridium cylinder kept near Paris.
What is a gram?
A gram is one thousandth of a kilogram. Recipes, nutrition labels, postage and jewellery weights use grams in metric countries.
What is a milligram?
A milligram is one thousandth of a gram. Medicine strengths, vitamins and minerals on supplement labels are usually given in milligrams.
Common mistakes to avoid
Confusing fluid ounces (volume) with ounces (weight), using troy ounces for food or regular ounces for gold, and mixing u.s. short tons, uk long tons and metric tonnes.
Formula
1 kg = 1,000 g1 kg = 1,000,000 mg1 kg = 0.001 t1 kg = 2.2046226 lb1 kg = 35.273962 ozWorked example
Inputs — From: 1 kg.
Results — To = 1,000 g; Milligrams = 1,000,000 mg; Tonnes = 0.001 t; Pounds = 2.20462262 lb; Ounces = 35.27396195 oz; Stone = 0.15747304 st; Short tons = 0.00110231 US ton.
Key terms
- Avoirdupois pound
- The everyday pound of 16 ounces, 0.45359237 kg.
- Troy ounce
- 31.1034768 g, the unit for precious metals.
Frequently asked questions
Is weight the same as mass?
In everyday use, yes. Physically, mass is measured in kilograms and weight is the force of gravity on it, measured in newtons.
What is a troy ounce?
31.1034768 g, used for gold, silver and platinum; about 10% heavier than a regular ounce.
How many pounds in a stone?
14 lb, about 6.35 kg.
How do I change the units?
Pick any unit in the From and To menus. The value is converted in place, and the heading changes to show your conversion, for example “Kilograms to Grams Converter”.
Can I type into any field?
Yes. Every field is editable, so you can start from whichever unit you have.
How many units can I convert between?
19 mass units, from the everyday to the specialised.
Which units are exact?
All factors here are exact by definition except astronomical and similar reference values, which use internationally agreed constants.
What formula does the Weight Converter use?
1 kg = 1,000 g.