Conversion formula

The conversion factor from fluid ounces to cups is 0.125, which means that 1 fluid ounce is equal to 0.125 cups:

1 fl oz = 0.125 cup

To convert 643.5 fluid ounces into cups we have to multiply 643.5 by the conversion factor in order to get the volume amount from fluid ounces to cups. We can also form a simple proportion to calculate the result:

1 fl oz → 0.125 cup

643.5 fl oz → V_(cup)

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

V_(cup) = 643.5 fl oz × 0.125 cup

V_(cup) = 80.4375 cup

The final result is:

643.5 fl oz → 80.4375 cup

We conclude that 643.5 fluid ounces is equivalent to 80.4375 cups:

643.5 fluid ounces = 80.4375 cups

Alternative conversion

We can also convert by utilizing the inverse value of the conversion factor. In this case 1 cup is equal to 0.012432012432012 × 643.5 fluid ounces.

Another way is saying that 643.5 fluid ounces is equal to 1 ÷ 0.012432012432012 cups.

Approximate result

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

643.5 fl oz ≅ 80.438 cup

An alternative is also that one cup is approximately zero point zero one two times six hundred forty-three point five fluid ounces.

Conversion table

fluid ounces to cups chart

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