Gal to Kg Converter

What Is the Gal to Kg Converter?

The Gal to Kg Converter is a free online tool that converts US gallons to kilograms and kilograms back to gallons using substance density. Gallons measure volume while kilograms measure mass, so the conversion depends entirely on what liquid or material you are measuring. Water, milk, gasoline, and honey all have different densities, meaning one gallon of each weighs a different number of kilograms.

This tool defaults to water density and supports common liquids plus custom density input for any substance. Results update in real time and include grams, pounds, and liters where applicable.

How to Use This Converter

1. Select direction: Choose gallons to kilograms or kilograms to gallons.
2. Choose a substance: Pick water, milk, gasoline, honey, or another preset.
3. Custom density: Select Custom Substance to enter density in $kg/L$.
4. Enter the value: Type gallons or kilograms.
5. View results: See kilograms, grams, pounds, or liters instantly.

Conversion Formula

The conversion between gallons and kilograms uses the standard density relationship. One US gallon equals $3.78541$ liters:

$$\text{kg} = \text{gal} \times 3.78541 \times \rho$$

Where $\rho$ is density in $kg/L$. For water at room temperature, density is about $1\ kg/L$, so one US gallon of water weighs about $3.79\ kg$. Five gallons of water weigh about $18.93\ kg$.

To convert kilograms to gallons, rearrange the formula:

$$\text{gal} = \frac{\text{kg}}{3.78541 \times \rho}$$

Density Reference Table

For related conversions, try our Gallons to Pounds Converter, Gallons to Grams Converter, or Volume Converter.