# How do I convert oz to kg?

Converts ounces (oz) to kilograms (kg) and back, with the exact unit definitions.

- Page: https://www.acalculator.org/convert/oz-to-kg
- JSON spec: https://www.acalculator.org/convert/oz-to-kg.json
- Version: 5519de5750d8

## Default answer

Example with the default inputs (Ounces (oz) 1): 1 oz = 0.02835 kg.

## Inputs

| Key | Label | Description |
| --- | --- | --- |
| value | Ounces (oz) | The amount in ounces to convert. |
| result | Kilograms (kg) | The same amount in kilograms. |

## Outputs

| Key | Label | Description |
| --- | --- | --- |
| value | Ounces (oz) | The amount in ounces to convert. |
| result | Kilograms (kg) | The amount in kilograms. |

## Method

kg = oz × 0.028349523125

## Assumptions

- 1 ounce = 0.028349523125 kilograms, from the exact definitions in NIST SP 811.
- Ounces here are avoirdupois ounces, a weight: 1 oz = 1/16 lb = 28.349523125 g. A US fluid ounce is a volume.
- The answer shows at most 6 decimal places; the calculation keeps full precision.

## Worked examples

1. value = 1 gives result = 0.02835. Source: Exact unit definitions in NIST SP 811 (2008), Appendix B.8.
2. value = 16 gives result = 0.453592. Source: Exact unit definitions in NIST SP 811 (2008), Appendix B.8.
3. result = 0.453592 gives value = 16. Source: Exact unit definitions in NIST SP 811 (2008), Appendix B.8.

## FAQ

### How many kilograms are in a ounce?

1 ounce is 0.02835 kilograms, from the exact unit definitions (NIST SP 811).

### How do I convert oz to kg?

Multiply by 0.02835: kg = oz × 0.028349523125. For example, 1 oz × 0.02835 = 0.02835 kg.

### How do I convert kg back to oz?

Multiply by 35.273962, or type the kilograms into the second box and the converter works it out. 1 kilogram is 35.273962 ounces.

### Is an ounce here a weight or a volume?

A weight: the avoirdupois ounce, 1/16 of a pound (28.349523125 g exactly). A US fluid ounce (29.57 mL) measures volume, as on cups-to-ounces pages.

## Sources

- NIST SP 811 (2008), Guide for the Use of the International System of Units, Appendix B.8. https://www.nist.gov/pml/special-publication-811