gram (g)

1 gram = 0.001 kilograms

What is gram?

A gram is a metric unit of mass equal to one thousandth of a kilogram. It is widely used in cooking, food labelling, and the measurement of small quantities in science and pharmacy.

Notes: Metric unit

Real-world uses

Grams are used for food nutrition labelling, postal weight limits, cooking recipes (especially in baking where precision matters), and jewellery weights. Pharmacists measure drug dosages in grams and fractions thereof.

History

The gram was the original base unit of mass in the French metric system of 1795, defined as the mass of one cubic centimetre of water. It later became the base unit in the CGS system before the kilogram took precedence in SI.

Common mistakes

Confusing grams with grains (1 grain ≈ 0.065 g), a common error in pharmaceutical contexts. Also, mistaking "g" for "G" in digital contexts where G means giga.

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 gram to kilogram

To convert gram to kilogram, multiply the value by 0.001.

Conversion formula (from base unit)

x * 0.001

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: gram to kilogram
gramskilograms
0.10.0001
0.50.0005
10.001
20.002
50.005
100.01
250.025
500.05
1000.1
2500.25
5000.5
1,0001

Common values

Common values
gramskilograms
A paperclip1 gram0.001 kilograms
A smartphone175 grams0.175 kilograms
A bag of sugar1,000 grams1 kilogram
Average adult human70,000 grams70 kilograms
A small car1,200,000 grams1,200 kilograms

Full gram conversion table

Full gram conversion table
Unit Value Factor
kilogram1 g = 0.001 kg× 0.001
pound1 g = 0.00220462 lb× 0.00220462
ounce1 g = 0.03527396 oz× 0.03527396
tonne1 g = 0.000001 t× 0.000001
milligram1 g = 1,000 mg× 1,000
microgram1 g = 1,000,000 µg× 1,000,000
stone1 g = 0.00015747 st× 0.00015747
short ton (US)1 g = 0.0000011 short ton× 0.0000011
long ton (UK)1 g = 9.842065e-07 long ton× 9.842065e-07