## Conversion formula

The conversion factor from cubic feet to gallons is 7.4805194805226, which means that 1 cubic foot is equal to 7.4805194805226 gallons:

1 ft3 = 7.4805194805226 gal

To convert 21 cubic feet into gallons we have to multiply 21 by the conversion factor in order to get the volume amount from cubic feet to gallons. We can also form a simple proportion to calculate the result:

1 ft3 → 7.4805194805226 gal

21 ft3 → V(gal)

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

V(gal) = 21 ft3 × 7.4805194805226 gal

V(gal) = 157.09090909097 gal

The final result is:

21 ft3 → 157.09090909097 gal

We conclude that 21 cubic feet is equivalent to 157.09090909097 gallons:

21 cubic feet = 157.09090909097 gallons

## Alternative conversion

We can also convert by utilizing the inverse value of the conversion factor. In this case 1 gallon is equal to 0.0063657407407381 × 21 cubic feet.

Another way is saying that 21 cubic feet is equal to 1 ÷ 0.0063657407407381 gallons.

## Approximate result

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

21 ft3 ≅ 157.091 gal

An alternative is also that one gallon is approximately zero point zero zero six times twenty-one cubic feet.

## Conversion table

### cubic feet to gallons chart

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

cubic feet (ft3) gallons (gal)
22 cubic feet 164.571 gallons
23 cubic feet 172.052 gallons
24 cubic feet 179.532 gallons
25 cubic feet 187.013 gallons
26 cubic feet 194.494 gallons
27 cubic feet 201.974 gallons
28 cubic feet 209.455 gallons
29 cubic feet 216.935 gallons
30 cubic feet 224.416 gallons
31 cubic feet 231.896 gallons