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Getting seed in the ground at the right rate and spacing: seeding rate conversions, plant population, row and in-row spacing…
Turning a soil test into product: nutrient requirement to fertilizer product conversions, custom blends, lime and pH amendment…
Everything between the label rate and the boom: sprayer calibration, tank mixing, small-sprayer dilution, nozzle flow at…
Water math for growers and irrigation designers: crop water demand, run times, drip and sprinkler output rates, and pond volume…
Stocking and animal performance math for ranchers and small livestock owners: carrying capacity in animal units, grazing days…
Ration and forage inventory math: dry matter intake, Pearson square protein balancing, feed conversion, bale weight and how much…
In-field yield estimating and post-harvest handling: corn and soybean yield checks, moisture shrink, bin capacity, test weight…
Tractor and implement performance plus the per-acre economics that decide whether a field operation pays: drawbar and PTO power…
Consumer and contractor landscaping math: mulch, topsoil and sod quantities, lawn fertilizer and seed rates, plus tree height…
Most used in agriculture, livestock & landscaping
- Seeding Rate per Acre CalculatorPure live seed (PLS) basis — AOSA/AOSCA seed labelling conventionsGive this calculator the stand you are aiming for and it returns the seed you actually have to buy: pounds per acre, total…
- Plant Population per Acre Calculator1/1,000-acre stand-count method (Cooperative Extension)This calculator answers two different questions with the same arithmetic. Before planting, it converts a row width and an…
- Field Acreage & Area CalculatorU.S. survey acre = 43,560 square feet (Public Land Survey System)Enter the dimensions you actually measured and this calculator returns the area in acres, hectares, square feet, square yards…
- Fertilizer NPK Requirement CalculatorGuaranteed analysis labelling (AAPFCO Official Publication)A soil test tells you to apply 150 pounds of nitrogen, 60 of P 2 O 5 and 60 of K 2 O per acre. It does not tell you how much…
- Sprayer Calibration (Gallons per Acre) Calculator1/128-acre catch methodThis calculator tells you what your boom sprayer is actually putting out, in gallons per acre, rather than what the rate…
- Spray Tank Mix CalculatorFIFRA — the pesticide label is the law (7 U.S.C. §136j)A boom sprayer is loaded by the tank, but labels are written by the acre. This calculator converts between them: enter your…
- Herbicide per Gallon (Backpack Sprayer) CalculatorFIFRA — the pesticide label is the law (7 U.S.C. §136j)Herbicide labels give you a rate per acre, but a backpack sprayer holds gallons. This calculator bridges the two: enter the…
- Irrigation Run Time CalculatorIrrigation Association audit methodThis calculator answers the only irrigation question most people actually have: how many minutes should this zone run? Give it…
- Sprinkler Precipitation Rate CalculatorIrrigation Association precipitation-rate method (96.3 constant)Precipitation rate is how fast a sprinkler zone applies water, in inches per hour, and it is the number that turns a watering…
- Cattle Weight Calculator (Heart Girth Tape)Girth-and-length rule (Schaeffer's formula)Wrap a tape around the animal just behind the front legs, measure from the point of the shoulder to the pin bone, and this…
- Horse Weight & Feed Requirement CalculatorCarroll & Huntington girth-length equation; NRC Nutrient Requirements of Horses (6th rev. ed.)Two measurements — heart girth and body length — estimate a horse's weight closely enough for feeding, conditioning and most…
- Livestock Gestation & Due Date CalculatorEnter the service date and this calculator projects the due date for cattle, horses, sheep, goats, pigs and camelids, using…