kilogram (kg)

1 kilogram = 1,000 grams

What is kilogram?

The kilogram is the SI base unit of mass. It is used globally as the standard for measuring weight and mass in science, industry, trade, and everyday life.

Notes: Base unit for mass

Real-world uses

The kilogram is the SI base unit of mass, used universally in science, commerce, and daily life outside the US. Grocery items, body weight in medical settings, and shipping weights are measured in kilograms across most of the world.

History

Originally defined in 1795 as the mass of one litre of water at 4°C. A platinum-iridium cylinder served as the standard from 1889 until 2019, when the kilogram was redefined in terms of the Planck constant, ending reliance on a physical artefact.

Common mistakes

Confusing mass (kg) with weight (newtons)—a kilogram measures mass, not force. Also, assuming 1 kg equals exactly 2 pounds; it is actually about 2.205 pounds.

When is this conversion used?

Body weight, grocery items, and luggage limits are commonly expressed in kilograms in most countries and pounds in the US and UK, making this one of the most frequently needed mass conversions. Cooking recipes and food packaging often switch between grams and ounces, especially when adapting recipes from different culinary traditions.

How to convert kilogram to gram

To convert kilogram to gram, multiply the value by 1,000.

Conversion formula (from base unit)

x * 1.0

Measurement standards

The kilogram is defined by fixing the Planck constant to exactly 6.62607015 × 10⁻³⁴ joule-seconds, as established at the 26th General Conference on Weights and Measures in 2018. This ended the last SI definition based on a physical artefact.

Did you know?

The International Prototype of the Kilogram, a platinum-iridium cylinder stored near Paris since 1889, was found to have drifted by about 50 micrograms relative to its copies over a century — roughly the mass of a fingerprint.

Quick reference: kilogram to gram
kilogramsgrams
0.1100
0.5500
11,000
22,000
55,000
1010,000
2525,000
5050,000
100100,000
250250,000
500500,000
1,0001,000,000

Common values

Common values
kilogramsgrams
A paperclip0.001 kilograms1 gram
A smartphone0.175 kilograms175 grams
A bag of sugar1 kilogram1,000 grams
Average adult human70 kilograms70,000 grams
A small car1,200 kilograms1,200,000 grams

Full kilogram conversion table

Full kilogram conversion table
Unit Value Factor
gram1 kg = 1,000 g× 1,000
pound1 kg = 2.20462262 lb× 2.20462262
ounce1 kg = 35.27396195 oz× 35.27396195
tonne1 kg = 0.001 t× 0.001
milligram1 kg = 1,000,000 mg× 1,000,000
microgram1 kg = 999,999,999.99999988 µg× 999,999,999.99999988
stone1 kg = 0.15747304 st× 0.15747304
short ton (US)1 kg = 0.00110231 short ton× 0.00110231
long ton (UK)1 kg = 0.00098421 long ton× 0.00098421