Kilograms to Grams Converter

Kilograms to Grams

Convert kilograms (kg) to grams (g). Both measure mass and weight, and the conversion comes up in cooking, shipping, fitness work.

The Formula

``grams = kilograms × 1000 kilograms = grams × 0.001`

One kilogram is 1,000 grams, and one gram is 0.001 kilograms.

`Conversion Table`

Kilograms	Grams
1 kg	1,000 g
2 kg	2,000 g
5 kg	5,000 g
10 kg	10,000 g
25 kg	25,000 g
50 kg	50,000 g
100 kg	100,000 g
500 kg	500,000 g
1,000 kg	1,000,000 g

`The Other Direction`

Grams	Kilograms
1 g	0.001 kg
2 g	0.002 kg
5 g	0.005 kg
10 g	0.01 kg
25 g	0.025 kg
50 g	0.05 kg
100 g	0.1 kg
500 g	0.5 kg
1,000 g	1 kg

`What Each Unit Is`

Kilograms (kg) — defined since 2019 by fixing the Planck constant — the SI base unit of mass. Originally the mass of a litre of water, then a platinum-iridium cylinder near Paris until 2019.

Grams (g) — one thousandth of a kilogram. The metric unit for small masses; cooking, nutrition and postage all work in grams.

`A Sense of Scale`

A litre of water is 1 kg


A laptop is 1.5–2 kg
Checked baggage allowance is often 23 kg
A paperclip is about 1 g
A sheet of A4 is 5 g
A tennis ball is 58 g


Precision
The factor 1000 is exact by international agreement, not a rounded approximation. Any imprecision in a result comes from your input, not the conversion.
In Code

`javascript const kilogramToGram = (value) => value * 1000;``

Where This Conversion Comes Up

Cooking
Shipping
Fitness
Medicine
Manufacturing

How Many Decimals Do You Need?

Rounding the factor costs accuracy, and how much depends on the factor. Converting 137 kg with the factor truncated at each decimal place:

Decimals kept	Factor	137 kg becomes	Error
0	1000	137,000	—
1	1000	137,000	—
2	1000	137,000	—
3	1000	137,000	—
4	1000	137,000	—

A rule that holds for any conversion: round once, at the end. Rounding the factor and then multiplying compounds the error through every subsequent calculation, while carrying full precision and rounding the final answer does not.

The right number of significant figures is set by your input, not by the converter. If you measured kilograms to three significant figures, the answer in grams is only good to three — writing more digits claims precision the measurement never had.

Frequently Asked Questions

How do I convert kilograms to grams?

Multiply by 1000. For example, 10 kg is 10,000 g. Going the other way, divide by 1000 or multiply by 0.001.

How many grams are in one kilogram?

Exactly 1,000 grams in one kilogram, so 25 kg is 25,000 g and 100 kg is 100,000 g. Going the other way, one gram is 0.001 kilograms.

Is the kilograms to grams conversion exact?

The factor 1000 is **exact** by international agreement, not a rounded approximation. Any imprecision in a result comes from your input, not the conversion.

Kilograms to Grams Converter