Definitive Fertilizer Calculator
For precise, professional crop nutrition and cost management.
Professional Recommendation
Fast, Free, Private Fertilizer Calculator
Calculate precise N‑P‑K fertilizer rates, split applications, and costs for crops worldwide. Top, fast, best, and lifetime free your information is 100% confidential and secure (processing is done locally in your browser).
Why people love this fertilizer calculator
Accurate N‑P‑K planning
Enter target nutrients and get exact Urea/DAP/MOP or custom blend rates in kg/ha or lbs/acre.
Soil-type adjustments
Account for sandy, clay, and loamy soils to optimize nutrient efficiency and reduce losses.
Split applications
Plan base and top-dress passes (e.g., N as Urea) to improve uptake and manage risk.
Cost calculator
Estimate total fertilizer needs and budget using local prices for Urea, DAP, MOP, or blends.
Crop presets
Start faster with presets for Corn/Maize, Wheat, Rice (Paddy), Potato, and Soybean.
Private by design
No uploads, no tracking everything runs locally on your device.
Popular uses worldwide
Farm nutrient planning
Balance N, P, and K by crop, soil, and field size; export in kg/ha or lbs/acre.
Input cost budgeting
Estimate fertilizer costs with local market prices and custom blends.
Extension & consulting
Create fast, consistent recommendations for growers and training programs.
Precision & VR planning
Support variable-rate scripts with clean N‑P‑K targets and split timing.
Education & labs
Demonstrate P2O5/K2O conversions and fertilizer math clearly.
Smallholders to enterprise
From backyard plots to large farms simple, fast, and accurate.
How to calculate fertilizer rates
- Select your crop preset (or “Custom”), soil type, and field size (hectares or acres).
- Enter target N, P, and K (elemental) the tool converts P to P₂O₅ and K to K₂O automatically.
- Optional: enable Split Application to top-dress part of the N (often as Urea).
- Enter local prices for Urea, DAP, MOP, or define a custom blend and strategy (P‑based or K‑based).
- Click “Calculate” to get rates, total amounts, nutrient balance, and costs.
Global availability (GEO)
Built for the USA, UK, Canada, Australia, India, the EU (Germany, France, Spain, Italy, Netherlands), Middle East (UAE, Saudi Arabia), Asia (Singapore, Malaysia, Philippines, Indonesia, Japan, South Korea), Africa (Nigeria, South Africa, Egypt), and Latin America (Brazil, Mexico, Argentina). Use hectares or acres, and view results in kg/ha or lbs/acre. English variants supported: fertilizer (US/CA) and fertiliser (UK/IN/AU).
Frequently Asked Questions
Is it private and secure?
Yes. Everything runs locally in your browser. Your data never leaves your device.
Elemental P vs P₂O₅? K vs K₂O?
Targets are elemental P and K. The tool converts to P₂O₅ (×2.291) and K₂O (×1.205) for fertilizer sources.
Which fertilizers are included?
Urea (46‑0‑0), DAP (18‑46‑0), MOP (0‑0‑60), and custom blends with N‑P₂O₅‑K₂O percentages.
Can I do split applications?
Yes, typically for N. P and K are often applied at planting; adjust as local guidance suggests.
Is it really free?
Yes lifetime free and unlimited. No signups, no paywalls, no watermarks.
Does this replace soil tests?
No. Always use recent soil tests and local recommendations for final decisions.
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