Sprayer Calibration Calculator
Dial in your ground speed, nozzle output, and gallons per acre — then plan your tank. Every number updates as you type.
Check your ground speed
Drive the measured distance in the gear and RPM you'll spray in, with a full tank. Run it twice and average.
MPH = (distance in feet ÷ seconds) × 0.681818
Gallons per acre from your nozzle output
GPA = (5940 × GPM per nozzle) ÷ (MPH × nozzle spacing in inches)
Nozzle output needed to hit a target rate
GPM per nozzle = (GPA × MPH × nozzle spacing in inches) ÷ 5940 · Total = (GPA × MPH × swath ft) ÷ 495
Adjust output with pressure
Flow does not change in proportion to pressure. Doubling flow takes roughly four times the pressure. Stay inside the nozzle manufacturer's rated range — going outside it changes droplet size and drift, not just volume.
Q2 / Q1 = square root of (P2 / P1)
1/128-acre field check
Mark off that distance. Drive it at spray speed and time how long it takes. Then park, run the sprayer at spray pressure for exactly that many seconds, and catch the output in a measuring jug — one nozzle for a broadcast boom, every nozzle on one row for an orchard or vineyard rig.
Distance (ft) = 4083.75 ÷ nozzle spacing in inches
1/128 acre × 128 oz per gallon → ounces caught = gallons per acre
Tank and mix planner
Always follow the product label. The label rate per acre does not change with your water volume.
Acres per tank = tank ÷ GPA · Product per tank = acres per tank × rate per acre · Tanks = block acres ÷ acres per tank