FullCalculator

Irrigation Water Calculator

Irrigation Water

Estimate irrigation water needs for crops per acre.

Formula

Irrigation = (ET x 7 - Rainfall) / Efficiency

Frequently Asked Questions

What is ET rate?
ET is evapotranspiration, the rate at which a crop uses water through evaporation and transpiration.
What irrigation efficiency should I use?
Use 75% for sprinkler, 85% for center pivot, and 90% for drip irrigation.