Cubic Inches to Gallons Converter

Enter the volume in cubic inches below to get the value converted to gallons.


Result in Gallons:

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1 in³ = 0.004329 gal

Do you want to convert gallons to cubic inches?

How to Convert Cubic Inches to Gallons

To convert a measurement in cubic inches to a measurement in gallons, divide the volume by the following conversion ratio: 231 cubic inches/gallon.

Since one gallon is equal to 231 cubic inches, you can use this simple formula to convert:

gallons = cubic inches ÷ 231

The volume in gallons is equal to the volume in cubic inches divided by 231.

For example, here's how to convert 500 cubic inches to gallons using the formula above.
gallons = (500 in³ ÷ 231) = 2.164502 gal

Cubic inches and gallons are both units used to measure volume. Keep reading to learn more about each unit of measure.

What Is a Cubic Inch?

A cubic inch is a unit of volume equal to the space consumed by a cube with sides that are one inch in all directions. One cubic inch is equivalent to about 16.387 cubic centimeters or 0.554 fluid ounces.[1]

The cubic inch is a US customary and imperial unit of volume. A cubic inch is sometimes also referred to as a cubic in. Cubic inches can be abbreviated as in³, and are also sometimes abbreviated as cu inch, cu in, or CI. For example, 1 cubic inch can be written as 1 in³, 1 cu inch, 1 cu in, or 1 CI.

Learn more about cubic inches.

What Is a Gallon?

The US liquid gallon is a unit of fluid volume equal to four quarts, eight pints, or sixteen cups.[1] 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.

Cubic Inch to Gallon Conversion Table

Table showing various cubic inch measurements converted to gallons.
Cubic Inches Gallons
1 in³ 0.004329 gal
2 in³ 0.008658 gal
3 in³ 0.012987 gal
4 in³ 0.017316 gal
5 in³ 0.021645 gal
6 in³ 0.025974 gal
7 in³ 0.030303 gal
8 in³ 0.034632 gal
9 in³ 0.038961 gal
10 in³ 0.04329 gal
20 in³ 0.08658 gal
30 in³ 0.12987 gal
40 in³ 0.17316 gal
50 in³ 0.21645 gal
60 in³ 0.25974 gal
70 in³ 0.30303 gal
80 in³ 0.34632 gal
90 in³ 0.38961 gal
100 in³ 0.4329 gal
200 in³ 0.865801 gal
300 in³ 1.2987 gal
400 in³ 1.7316 gal
500 in³ 2.1645 gal
600 in³ 2.5974 gal
700 in³ 3.0303 gal
800 in³ 3.4632 gal
900 in³ 3.8961 gal
1,000 in³ 4.329 gal


  1. National Institute of Standards and Technology, Specifications, Tolerances, and Other Technical Requirements for Weighing and Measuring Devices, Handbook 44 - 2019 Edition,

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