Gallons to Kilograms Conversion Calculator
Enter the volume in gallons below to calculate the weight in kilograms.
Result: Kilograms
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How to Convert Gallons to Kilograms
Since gallons are a unit of volume and kilograms are a unit of mass, which are different physical quantities, we need to know one more physical quantity of the ingredient or substance to convert between them. In this case, we need to account for the density of the substance whenever we do a conversion.
Therefore, to convert between gallons and kilograms of an ingredient or substance, we must either multiply or divide by its density, depending on which direction we are performing the conversion.
Gallons to Kilograms Formula
To convert a measurement in gallons to kilograms, multiply the volume by the density of the ingredient or material. Note that in order for this to work, the density must be in kilograms per gallon (kg/gal).
If the density is given in grams per milliliter (g/mL), then first multiply the density by 3.7854 to convert to kg/gal.
For a density given in g/mL, you can use this simple formula to convert:
kilograms = gallons × 3.7854 × density
Thus, the weight in kilograms is equal to the volume in gallons multiplied by 3.7854 times the density (in g/mL) of the ingredient, substance, or material.
For example, here's how to convert 5 gallons to kilograms for an ingredient with a density of 0.7 g/mL.
kilograms = 5 gal × 3.7854 × 0.7 g/mL = 13.2489 kg
How Many Kilograms Are in a Gallon?
The actual weight of a gallon will vary depending on the material's density. The conversion table below shows how many kilograms of various wet and dry ingredients are in a gallon.
| Volume in Gallons: | Weight in Kilograms of: | ||||
|---|---|---|---|---|---|
| Water | Milk | Cooking Oil | Gasoline | Diesel | |
| 1/4 gal | 0.946 kg | 0.975 kg | 0.833 kg | 0.7 kg | 0.804 kg |
| 1/2 gal | 1.893 kg | 1.949 kg | 1.666 kg | 1.401 kg | 1.609 kg |
| 3/4 gal | 2.839 kg | 2.924 kg | 2.498 kg | 2.101 kg | 2.413 kg |
| 1 gal | 3.785 kg | 3.899 kg | 3.331 kg | 2.801 kg | 3.218 kg |
| 2 gal | 7.571 kg | 7.798 kg | 6.662 kg | 5.602 kg | 6.435 kg |
| 3 gal | 11.36 kg | 11.7 kg | 9.993 kg | 8.404 kg | 9.653 kg |
| 4 gal | 15.14 kg | 15.6 kg | 13.33 kg | 11.21 kg | 12.87 kg |
| 5 gal | 18.93 kg | 19.5 kg | 16.66 kg | 14.01 kg | 16.09 kg |
So, one gallon of water weighs about 3.7854 kilograms and one gallon of milk weighs about 3.9 kilograms.
When to Convert Gallons to Kilograms
Gallons and kilograms are both commonly used to measure cooking ingredients.
For cooking applications, most chefs suggest measuring dry ingredients by weight rather than volume to improve accuracy in the measurements.[1] The density of dry ingredients can vary for a variety of reasons, such as compaction and clumping.
The best way to ensure an accurate conversion is to use a scale. When a scale is not available, a calculator like the one above is a good way to estimate the volume to weight conversion.
Another useful application of weight and volume conversions is chemistry. When performing chemical reactions by combining separate chemicals to produce a new chemical, one must know the exact amount of each chemical to add in order to maximize the yield of the reaction.
It is common to mix powdered chemicals with liquid, or aqueous, chemicals, and this is where it becomes very useful to convert between weights and volumes.[2]
A third application of weight and volume conversions is when shipping freight when calculating the volumetric weight for cargo and packages. Trucks, ships, and airplanes are limited in the amount of weight or volume they can transport, so if one of those quantities is known, but the limitation is on the other, then it becomes necessary to convert between the two so as not to overload the shipping vehicle.
Keep reading to learn more about each unit of measure.
What Is a Gallon?
The US liquid gallon is a unit of fluid volume equal to four quarts, eight pints, or sixteen cups.[3] The US liquid gallon should not be confused with the US dry gallon or the imperial gallon, which are different units of measure.
The gallon is a US customary unit of volume. Gallons can be abbreviated as gal; for example, 1 gallon can be written as 1 gal.
Learn more about gallons.
What Is a Kilogram?
One kilogram is equal to 1,000 grams, 2.204623 pounds, or 1/1,000 of a metric ton.
The formal definition of the kilogram changed in 2019. One kilogram was previously equal to the mass of the platinum-iridium bar, known as the International Prototype of the Kilogram, which was stored in Sèvres, France.
The 2019 SI brochure now defines the kilogram using the Planck constant, and it is defined using the meter and second.[4] It is equal to the mass of 1,000 cubic centimeters, or milliliters, of water.
The kilogram, or kilogramme, is the SI base unit for mass and is also a multiple of the gram. In the metric system, "kilo" is the prefix for thousands, or 103. Kilograms can be abbreviated as kg; for example, 1 kilogram can be written as 1 kg.
A kilogram is also frequently referred to as a unit of weight. While technically, a kilogram is a measure of mass, and weight is actually a measure of force, the two are equivalent as long as we are performing our calculations on Earth.
For example, an object with a mass of 1 kilogram weighs 1 kilogram on Earth, but only weighs one-sixth of that on the moon, yet still has the same mass.
Learn more about kilograms.
References
- National Institute of Standards & Technology, Culinary Measurement Tips, https://www.nist.gov/pml/owm/culinary-measurement-tips
- CK-12 Foundation, Introductory Chemistry (CK-12) - 12.6: Mass-Volume Stoichiometry, https://chem.libretexts.org/Bookshelves/Introductory_Chemistry/Introductory_Chemistry_(CK-12)/12%3A_Stoichiometry/12.06%3A_Mass-Volume_Stoichiometry
- National Institute of Standards and Technology, Specifications, Tolerances, and Other Technical Requirements for Weighing and Measuring Devices, Handbook 44 - 2019 Edition, https://nvlpubs.nist.gov/nistpubs/hb/2019/NIST.HB.44-2019.pdf
- International Bureau of Weights and Measures, The International System of Units, 9th Edition, 2019, https://www.bipm.org/documents/20126/41483022/SI-Brochure-9-EN.pdf