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 138 cubic inches into gallons we have to multiply 138 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

138 in3 → V_(gal)

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

V_(gal) = 138 in3 × 0.0043290043290138 gal

V_(gal) = 0.59740259740391 gal

The final result is:

138 in3 → 0.59740259740391 gal

We conclude that 138 cubic inches is equivalent to 0.59740259740391 gallons:

138 cubic inches = 0.59740259740391 gallons

Alternative conversion

We can also convert by utilizing the inverse value of the conversion factor. In this case 1 gallon is equal to 1.6739130434746 × 138 cubic inches.

Another way is saying that 138 cubic inches is equal to 1 ÷ 1.6739130434746 gallons.

Approximate result

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

138 in3 ≅ 0.597 gal

An alternative is also that one gallon is approximately one point six seven four times one hundred thirty-eight 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