Transparent watering calculation
Sprinkler Runtime Calculator
Convert a target watering depth and measured or manufacturer-provided precipitation rate into runtime. The calculator shows the formula so the result can be checked instead of treated like a black box.
Runtime inputs
Enter the values you actually know.
If you do not know the precipitation rate, measure it or use documented data for the installed nozzle or sprinkler configuration.
Inches for the watering event or period you are calculating.
Inches per hour. Use a measured or documented value.
Used only to split the target across multiple watering days.
Used only to divide the daily runtime into equal cycles.
Runtime estimate
Total runtime40 minfor the full target depth
Per watering day20 minacross 2 days
Per cycle20 min1 cycle per day
0.50 in ÷ 0.75 in/hr × 60 = 40 minutes
What this calculator does
It converts water depth and precipitation rate into time, then divides that total across the watering days and cycles you enter.
What it does not decide
It does not choose the correct watering target for your lawn, soil, climate, local restrictions, or plant needs. Those inputs must come from your situation.