Science & Environment
Rainwater Harvesting Tank Volume Calculator
Estimate harvestable rainwater volume from roof catchment area, rainfall and runoff efficiency.
Your inputs
Change any value to update the result instantly.
Harvestable volume
3,187.5 L
Volume in cubic meters
3.188 m³
Recommended tank size
3.83 m³
Runoff coefficient used
0.85
Formula and working
V (L) = area (m²) × rainfall (mm) × runoff coefficient
- 1
Collect the inputs
Roof catchment area = 150 m²; Rainfall event depth = 25 mm; Runoff coefficient = 0.85
- 2
Apply the formula
V (L) = area (m²) × rainfall (mm) × runoff coefficient
- 3
Result
Harvestable volume = 3,187.5 L
Frequently asked questions
Important limitation
This is an educational estimate based only on the values and formula shown. Verify current rates, rules, units, and professional standards before relying on the result. It is not personalized financial or investment advice.
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