Conversion formula

The conversion factor from gallons to cubic inches is 230.99999999949, which means that 1 gallon is equal to 230.99999999949 cubic inches:

1 gal = 230.99999999949 in3

To convert 21 gallons into cubic inches we have to multiply 21 by the conversion factor in order to get the volume amount from gallons to cubic inches. We can also form a simple proportion to calculate the result:

1 gal → 230.99999999949 in3

21 gal → V_(in3)

Solve the above proportion to obtain the volume V in cubic inches:

V_(in3) = 21 gal × 230.99999999949 in3

V_(in3) = 4850.9999999894 in3

The final result is:

21 gal → 4850.9999999894 in3

We conclude that 21 gallons is equivalent to 4850.9999999894 cubic inches:

21 gallons = 4850.9999999894 cubic inches

Alternative conversion

We can also convert by utilizing the inverse value of the conversion factor. In this case 1 cubic inch is equal to 0.00020614306328637 × 21 gallons.

Another way is saying that 21 gallons is equal to 1 ÷ 0.00020614306328637 cubic inches.

Approximate result

For practical purposes we can round our final result to an approximate numerical value. We can say that twenty-one gallons is approximately four thousand eight hundred fifty-one cubic inches:

21 gal ≅ 4851 in3

An alternative is also that one cubic inch is approximately zero times twenty-one gallons.

Conversion table

gallons to cubic inches chart

For quick reference purposes, below is the conversion table you can use to convert from gallons to cubic inches