Free spray volume calculator for agriculture. Calculate GPA (gallons per acre), nozzle output (GPM), travel speed, and sprayer calibration. Includes boom sprayer, airblast, and backpack settings.
Flat Fan (Standard)
Recommended Pressure: 30-60 PSI
Drift Potential: Medium
Best For: Broadcast herbicide applications
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Accurate spray calibration ensures proper pesticide application, effective coverage, and regulatory compliance. Our calculator determines gallons per acre (GPA), nozzle output (GPM), travel speed, and nozzle spacing—the four key variables in the sprayer calibration equation.
Spray volume (GPA) is the amount of spray mix applied per acre. It's determined by nozzle output, travel speed, and nozzle spacing. The standard formula relates these variables so you can solve for any one when you know the other three. Proper calibration ensures you apply the correct rate of product.
GPA Calculation Formula
GPA = (GPM × 5,940) ÷ (MPH × Nozzle Spacing in inches)Pesticide labels specify application rates. Calibration ensures you apply the correct amount per acre as legally required.
Too little spray means poor coverage and pest survival. Too much wastes product and may damage crops.
Accurate application avoids wasting expensive pesticides and reduces repeat treatments.
Proper calibration minimizes off-target drift and reduces environmental contamination.
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The constant 5,940 converts gallons per minute to gallons per acre, accounting for the area covered per minute at different speeds and spacings. It simplifies the math: 5,940 = 43,560 sq ft/acre ÷ (660 ft/min per MPH ÷ 12 in/ft).