This free converter changes grams (g) into kilograms (kg) and back again, updating live as you type. It’s useful for recipes, parcel and luggage weights, lab measurements, and any time you switch between grams and kilograms.
How it works
The kilogram is the SI base unit of mass, and the gram is defined as exactly one thousandth of it. So the relationship is fixed and exact:
kilograms = grams ÷ 1000 (and grams = kilograms × 1000)
Type in the grams field to divide, or the kilograms field to multiply. Because the factor is exact, results are precise with no rounding error for everyday values.
Example
A bag of flour weighs 2500 grams and you want it in kilograms:
2500 ÷ 1000 = 2.5 kg
So 2500 grams is two and a half kilograms.
| Grams (g) | Kilograms (kg) |
|---|---|
| 100 g | 0.1 kg |
| 500 g | 0.5 kg |
| 1000 g | 1 kg |
| 2500 g | 2.5 kg |
All calculations run entirely in your browser — no data is sent to any server.
Common grams-to-kilograms reference values
| Grams (g) | Kilograms (kg) | Typical context |
|---|---|---|
| 250 g | 0.25 kg | Standard butter block (UK/EU) |
| 454 g | 0.454 kg | One US pound |
| 500 g | 0.5 kg | Half a kilogram of mince or pasta |
| 1,000 g | 1 kg | 1 litre of water, standard flour bag |
| 1,500 g | 1.5 kg | Common luggage item weight |
| 2,500 g | 2.5 kg | Typical bag of rice |
| 10,000 g | 10 kg | Standard checked luggage limit per item |
Where this conversion comes up in everyday life
Recipes and food. Many European recipes list ingredients in grams, while US nutrition labels show serving sizes in grams but list product totals in kilograms. Converting between the two is especially common when scaling up batch recipes.
Parcels and postage. Parcel carriers typically accept weights in kilograms, but kitchen scales and postal scales often display in grams. A parcel weighing 2,350 g is 2.35 kg — just divide by 1,000.
Fitness and body weight. Gym equipment and nutrition apps often mix units: a dumbbell may be listed as 500 g but your total programme volume is tracked in kilograms. Consistent unit use avoids calculation errors in training logs.
Scientific measurements. Chemistry and physics labs commonly work in grams for small quantities and convert to kilograms when presenting results in SI units (the Newton, Joule, and Pascal are all defined in kg-metres-seconds). A mass of 3,250 g is simply 3.25 kg in SI notation.
Is this the same as a milligrams-to-grams conversion?
No — but the same factor applies. Milligrams (mg) to grams is also ÷ 1,000, and tonnes to kilograms is × 1,000. The metric system uses consistent powers of ten: milli- means one thousandth and kilo- means one thousand. So the entire scale is: 1 tonne = 1,000 kg = 1,000,000 g = 1,000,000,000 mg. The converter on this page handles the gram-kilogram step specifically.