Aerial view of agricultural field

Fertilizer & Seed Calculator

Calculate exact fertilizer quantities for your fields. Get instant results with crop-specific presets for corn, wheat, soybeans, rice, and cotton.

Calculate Fertilizer Needs

Get precise fertilizer quantities for your field

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Don't know your field area? Measure it on a map
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Enter Field Details

Fill in your field area and crop type to see fertilizer calculations

About Fertilizer Calculation

Accurate fertilizer calculation is essential for maximizing crop yields while minimizing costs and environmental impact. This calculator helps farmers determine precise fertilizer quantities based on field area and application rates.

Common Application Rates by Crop

Corn (Nitrogen):120-180 lbs/acre (135-202 kg/hectare)
Wheat (Nitrogen):80-120 lbs/acre (90-135 kg/hectare)
Soybeans (Nitrogen):30-60 lbs/acre (34-67 kg/hectare)
Rice (Nitrogen):100-140 lbs/acre (112-157 kg/hectare)
Cotton (Nitrogen):90-130 lbs/acre (101-146 kg/hectare)

Why Use This Calculator?

  • ✓ Crop-Specific Presets - Auto-filled rates for major crops
  • ✓ Multiple Units - Works with acres, hectares, lbs, kg
  • ✓ Instant Calculations - Real-time results as you type
  • ✓ Mobile Friendly - Use in the field on your phone
  • ✓ Cost Savings - Avoid over or under-application
  • ✓ 100% Free - No registration required

Frequently Asked Questions

How much fertilizer do I need per acre?

Fertilizer needs vary by crop. Corn typically needs 120-180 lbs/acre nitrogen, wheat 80-120 lbs/acre, soybeans 30-60 lbs/acre. Always base rates on soil test results for your specific field.

What is the application rate for fertilizer?

Application rate is the amount of fertilizer per unit area, commonly measured in lbs/acre or kg/hectare. It varies by crop, soil conditions, target yield, and nutrient content.

How do I calculate fertilizer cost?

First calculate total fertilizer needed using this calculator, then multiply by the price per unit (lb, kg, or ton) from your supplier to get total cost.

Should I split fertilizer applications?

Split applications often improve fertilizer efficiency and reduce runoff risk. Common practice is to apply part at planting and part during crop growth stages (e.g., side-dress for corn).

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