Science-based farming starts with accurate calculations. Planting, land, livestock, and general tools — all free, no registration required.
Calculate seed requirement from spacing & 1000-grain weight
N-P-K requirements from target yield & efficiency
Multiple method or ppm concentration for accurate mixing
Water requirement & irrigation time by soil moisture
Key growth stages & harvest date from planting date
Yield from plant population × grains/ear × test weight
Germination rate test & seeding rate adjustment
Ventilation rate & duration for temp/humidity control
Tree spacing, trees/ha & seedling requirement
Herbicide amount & water volume for pre/post-emergence
Daily & seasonal water needs by crop, stage & ET
Pre-harvest interval & safe harvest date calculator
Optimal planting dates from soil temperature
Daily feed intake & protein needs for pigs, poultry, cattle
FCR calculation & profitability analysis for livestock/aqua
Optimal density & max capacity for barns and pens
Fish/shrimp stocking density, seed & feed requirements
Accurate drug dosing by weight, water, or feed mixing
Planting/harvest dates, intervals, and farm scheduling
$/kg ↔ $/lb ↔ $/ton conversion & total value
°C ↔ °F ↔ K conversion & dew point calculation
Monthly payment, total interest & repayment calculation
Estimate direct payments, insurance & conservation benefits
Rotation sequences, area allocation & planting schedules
Science-based articles to help you farm smarter. From soil testing to irrigation scheduling.
Interpret pH, N-P-K, organic matter, CEC, and base saturation to optimize your fertilizer program.
Calculate runtime based on emitter flow, crop water needs, soil type, and efficiency.
Break down N-P-K costs, compare products, and find strategies to reduce fertilizer expenses.
Farm Tools Calculator provides free, science-based online calculators for farmers, agronomists, agricultural students, and anyone involved in crop and livestock production. Our tools cover the full farming cycle — from planting and fertilization to harvest and marketing.
All calculations are based on established agricultural formulas and reference data. Results are estimates intended for planning purposes — always consult local agricultural extension services and qualified agronomists for site-specific recommendations.
We regularly add new tools and update existing ones. If you have suggestions for new calculators or improvements, we'd love to hear from you.