Conversion formula

The conversion factor from cups to gallons is 0.0625, which means that 1 cup is equal to 0.0625 gallons:

1 cup = 0.0625 gal

To convert 645 cups into gallons we have to multiply 645 by the conversion factor in order to get the volume amount from cups to gallons. We can also form a simple proportion to calculate the result:

1 cup → 0.0625 gal

645 cup → V_(gal)

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

V_(gal) = 645 cup × 0.0625 gal

V_(gal) = 40.3125 gal

The final result is:

645 cup → 40.3125 gal

We conclude that 645 cups is equivalent to 40.3125 gallons:

645 cups = 40.3125 gallons

Alternative conversion

We can also convert by utilizing the inverse value of the conversion factor. In this case 1 gallon is equal to 0.024806201550388 × 645 cups.

Another way is saying that 645 cups is equal to 1 ÷ 0.024806201550388 gallons.

Approximate result

For practical purposes we can round our final result to an approximate numerical value. We can say that six hundred forty-five cups is approximately forty point three one three gallons:

645 cup ≅ 40.313 gal

An alternative is also that one gallon is approximately zero point zero two five times six hundred forty-five cups.

Conversion table

cups to gallons chart

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