Rainwater Calculator

How much rain could your roof collect, and how far could that water go? Use local rainfall history to explore collection potential, tank sizing, and water supply through wet and dry months. Free to use.

New to rainwater harvesting? Learn the basics or explore the rainfall data.

1

Location

Find your property

2

Property Details

Enter home information

3

Results

View your analysis

Find Your Location

Enter your address or click on the map to select your property and get location-specific rainfall data.

Can't find your address? Use the map to select your location

Rainwater Site Planner

Measure your roof catchment on aerial imagery, arrange multiple tanks, and compare round, rectangular, and slimline footprints before planning an installation.

Additional tools include custom rainfall analysis for your own data and a firm-yield calculator.

Plan Your Site

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