Turn a chosen irrigation depth and measured sprinkler output into runtime and water use.
How this calculator works
Remaining depth = max(0, target − effective rainfall). Runtime = remaining depth ÷ measured application rate × 60. One millimetre over one square metre equals one litre. Collect water in evenly spaced catch cups for a measured duration and use average depth ÷ elapsed hours as the application rate. Choose a target appropriate to grass, soil, season and local restrictions; the sample is not a watering recommendation. Rainfall is entered manually. This tool does not fetch weather or account for distribution losses. Split runtime into soak cycles if runoff occurs.
Units and inputs
Use measured inputs and replace the demonstration values. 1 ft = 0.3048 m; 1 sq ft = 0.09290304 m²; 1 inch = 25.4 mm; 1 US gallon = 3.785411784 litres. All entered prices must use the same currency. Zero prices omit the optional budget.
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