About Rainwater Harvesting Calculator
Last updated: 2026-07-08
What We Do
Rainwater Harvesting Calculator is a free online tool that helps you estimate rainwater collection potential based on your roof area and local rainfall. All calculations and lookups run instantly in your browser — no account required, no personal data collected.
Our Mission
We believe water and sustainability information should be accessible to everyone. Government data, regulations, and technical specifications are often buried in hard-to-navigate sources. Rainwater Harvesting Calculator consolidates this information into a single, easy-to-use tool that gives you answers in seconds.
How It Works
Enter your details and get results immediately. Our calculations are based on publicly available data from official sources. We regularly review and update our data to ensure accuracy.
Data Sources
Our data comes from authoritative public sources, including:
- NOAA precipitation data
- State rainwater harvesting regulations
- American Rainwater Catchment Systems Association guidelines
Important Disclaimer
The results provided by Rainwater Harvesting Calculator are estimates for informational purposes only. They are not a substitute for professional advice. Always consult a qualified professional before making important decisions based on these results.
Privacy
We take your privacy seriously. Rainwater Harvesting Calculator does not collect personal information, require sign-ups, or sell data. Calculator inputs are processed entirely in your browser. Read our full privacy policy for details.
Contact
Have a question, found an error, or want to suggest an improvement? We'd love to hear from you. Email us at hello@rainwaterharvestcalc.com.