Rainfall & Irrigation Calculator
Calculate lawn irrigation needs based on rainfall, lawn size, and target watering. See weekly water deficit, watering time, and cost.
Inputs
sq ft
inches
in/week
in/hour
Results
Water Deficit
0.5 in/week
Watering Time20 minutes
Gallons Needed/Week1,558
Est. Monthly Cost$31.15
How to Use This Calculator
- Enter your Lawn Area in square feet.
- Set the Weekly Rainfall your area has been receiving in inches.
- Enter the Target Watering amount in inches per week (most lawns need 1–1.5 inches).
- Set your Sprinkler Rate in inches per hour.
- Review the Water Deficit, required Watering Time in minutes, Gallons Needed per week, and Estimated Monthly Cost.
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