Rain Barrel & Roof Catchment Water Calculator

Calculate annual rainwater harvesting potential in gallons and cubic meters from roof area, precipitation depth, and runoff efficiency.

  • 100% free
  • Private in browser
  • No signup
  • No watermarks
Total Annual Yield (Gallons)
33,390
Yield per 1-Inch Storm (Gallons)
954
Barrels Filled per 1-Inch Storm
17.3
Total Harvest (Cubic Meters m³)
126.4

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About Rain Barrel & Roof Catchment Water Calculator

Calculate annual rainwater harvesting potential in gallons and cubic meters from roof area, precipitation depth, and runoff efficiency.

How to use Rain Barrel & Roof Catchment Water Calculator

  1. Enter your required input values into the fields.
  2. View the automatically calculated results in real time.

Key features

  • Instant client-side calculation
  • Real-time updates without page reloads
  • Private and secure: zero data leaves your browser

Frequently asked questions

Is this calculation free and private?
Yes, 100% of calculations execute locally in your web browser. No inputs or personal data are stored or transmitted.