Conversion formula

The conversion factor from cubic inches to gallons is 0.0043290043290138, which means that 1 cubic inch is equal to 0.0043290043290138 gallons:

1 in3 = 0.0043290043290138 gal

To convert 321 cubic inches into gallons we have to multiply 321 by the conversion factor in order to get the volume amount from cubic inches to gallons. We can also form a simple proportion to calculate the result:

1 in3 → 0.0043290043290138 gal

321 in3 → V_(gal)

Solve the above proportion to obtain the volume V in gallons:

V_(gal) = 321 in3 × 0.0043290043290138 gal

V_(gal) = 1.3896103896134 gal

The final result is:

321 in3 → 1.3896103896134 gal

We conclude that 321 cubic inches is equivalent to 1.3896103896134 gallons:

321 cubic inches = 1.3896103896134 gallons

Alternative conversion

We can also convert by utilizing the inverse value of the conversion factor. In this case 1 gallon is equal to 0.71962616822272 × 321 cubic inches.

Another way is saying that 321 cubic inches is equal to 1 ÷ 0.71962616822272 gallons.

Approximate result

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

321 in3 ≅ 1.39 gal

An alternative is also that one gallon is approximately zero point seven two times three hundred twenty-one cubic inches.

Conversion table

cubic inches to gallons chart

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