Rainfall Calculator

How to Use This Calculator

1. Enter the rainfall depth (inches, mm, or cm).
2. Enter the area (acres, square feet, square meters, or square kilometers).
3. The calculator displays total water volume in gallons, liters, cubic meters, and cubic feet.
4. Use this to plan rainwater harvesting, irrigation, or water management.

Rainfall Volume Formula

Volume is calculated from rainfall depth and area:

Example: 1 inch of rain on 1 acre: Volume = (1/12) ft × 43,560 ft² = 3,630 ft³ = 27,154 gallons = 102,789 liters. For 0.5 inches on 0.25 acres: Volume = (0.5/12) ft × 10,890 ft² = 453.75 ft³ = 3,394 gallons.

Full Description

Rainfall volume calculation helps you understand how much water falls on a given area during precipitation. This is essential for water management, flood prediction, irrigation planning, rainwater harvesting, and stormwater management. Understanding rainfall volume helps you plan drainage systems, storage capacity, and water usage.

Rainfall volume is simply the product of rainfall depth and area. For example, 1 inch of rain on 1 acre equals about 27,154 gallons of water. This volume can be substantial—even moderate rainfall can produce thousands of gallons of water over large areas. The calculator handles various units (inches, mm, cm for depth; acres, square feet, square meters, square kilometers for area) and converts to common volume units.

This calculator helps you determine rainfall volume. Enter rainfall depth and area, and it calculates total water volume. Use it to plan rainwater harvesting systems, estimate irrigation needs, understand flood potential, plan drainage, or calculate water resources. Rainfall volume calculations are essential for water management and planning!

Frequently Asked Questions