# Volume of Rainfall Calculator in Gallons

Using the rain water harvesting method people can collect rain water from the roofs. Our online volume of rainfall calculator in gallons helps you to calculate the collectable rainwater from the roof in gallons. Just enter the value of rain fall in inches and area in square feet. The product of rain fall, area and the number 0.5 is used to calculate rainwater collection in gallons.

### Example:

Find the rainfall collected in an area of 520 sq.ft where the average rainfall is about 6 inches?

#### Solution:

Volume of rainfall in gallons = 0.5 * 520 * 6

=1560 gallons