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Sprayer calibration calculator

Calibration tells you how many gallons your sprayer applies per acre (GPA) at a given nozzle flow, speed, and spacing. Getting it right keeps you on the label rate — under-applying wastes a trip, over-applying is illegal and unsafe.

How it works

GPA = 5,940 × GPM ÷ (MPH × swath in)

Enter your values to see the result and worked steps.

Example

0.5 gal/min · 4 mph · 20 in

Application rate: 37.13 gal/acre

How it's calculated

The standard formula is GPA = 5,940 × GPM ÷ (MPH × W), where W is the nozzle spacing in inches. The constant 5,940 carries the unit conversions among acres (43,560 sq ft), feet per minute (88 ft/min per mph), and inches to feet.

Worked example: a nozzle delivering 0.5 GPM at 4 mph on 20-inch spacing applies 5,940 × 0.5 ÷ (4 × 20) = 37.1 gal/acre.