# Grams to kilograms converter

> Convert grams to kilograms (grams to kg) with the exact factor, a conversion chart and worked steps.

Interactive version: https://www.calcopenly.com/conversion/grams-to-kg
Subject: Unit converters

Gram amounts commonly come from ingredient labels, kitchen scales and small parcels. When a shipping form or stock record expects a larger unit, preserve amounts below one whole unit as decimals. The conversion changes the label and number together; it does not change how much material you have.

One gram is exactly 0.001 kilograms, so 500 g is 0.5 kg. To convert grams to kg, multiply by 0.001; to convert back, multiply by 1,000.

The gram is one thousandth of a kilogram, the SI base unit of mass. Because both units are defined exactly, the factor above is exact and the results here carry no conversion error.

## Inputs

- **Grams (g)**

## Results

- Kilograms (kg) — main result
- Conversion
- 1 kg in grams (g)

## Formula

$$
\text{kilograms} = \text{grams} \times 0.001
$$

## Worked examples

### 500 g to kg

- Grams (g): 500 g
- **Kilograms: 0.5 kg**
- Checked against: Exact-fraction computation from the legal unit definitions (scripts/gen-pairs.py, Python fractions)

### 200 g to kg

- Grams (g): 200 g
- **Kilograms: 0.2 kg**
- Checked against: Exact-fraction computation from the legal unit definitions (scripts/gen-pairs.py, Python fractions)

### 2000 g to kg

- Grams (g): 2000 g
- **Kilograms: 2 kg**
- Checked against: Exact-fraction computation from the legal unit definitions (scripts/gen-pairs.py, Python fractions)

## Questions

### Is 500 grams half a kilogram?

Yes. Divide 500 by 1,000 to get 0.5 kg. When adding several gram amounts for a shipping total, add them first and divide the combined total once; do not round each small item to a whole kilogram.

### How many kilograms are in a gram?

One gram is exactly 0.001 kilograms. The gram is one thousandth of a kilogram, the SI base unit of mass.

### How do you convert grams to kg?

Multiply the number of grams by 0.001. For example, 500 g × 0.001 = 0.5 kg. To go the other way, divide by 0.001.

### How accurate is the grams to kilograms converter?

Accuracy depends on your inputs and the method's assumptions. Decimal arithmetic uses 50 significant digits, but estimates, numerical methods and source data can be less precise; the displayed rounding does not remove those limits. It is checked against 3 worked examples whose answers come from independent sources; for example, “500 g to kg” is checked against Exact-fraction computation from the legal unit definitions (scripts/gen-pairs.py, Python fractions).

### Where does the method come from?

NIST SP 811 (2008), Guide for the Use of the International System of Units, Appendix B; NIST Handbook 44, Appendix C: General tables of units of measurement; BIPM, The International System of Units (SI Brochure), 9th edition.

## Sources

- [NIST SP 811 (2008), Guide for the Use of the International System of Units, Appendix B](https://www.nist.gov/pml/special-publication-811)
- [NIST Handbook 44, Appendix C: General tables of units of measurement](https://www.nist.gov/pml/weights-and-measures/publications/nist-handbooks/handbook-44)
- [BIPM, The International System of Units (SI Brochure), 9th edition](https://www.bipm.org/en/publications/si-brochure)