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 138 gallons into cubic inches we have to multiply 138 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

138 gal → V_(in3)

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

V_(in3) = 138 gal × 230.99999999949 in3

V_(in3) = 31877.99999993 in3

The final result is:

138 gal → 31877.99999993 in3

We conclude that 138 gallons is equivalent to 31877.99999993 cubic inches:

138 gallons = 31877.99999993 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 3.1369596587057E-5 × 138 gallons.

Another way is saying that 138 gallons is equal to 1 ÷ 3.1369596587057E-5 cubic inches.

Approximate result

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

138 gal ≅ 31878 in3

An alternative is also that one cubic inch is approximately zero times one hundred thirty-eight 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