Farm Fertilizer Calculator
Quickly calculate fertilizer requirements for your farm — precise recommendations, transparent costs, and a plan you can act on today.
Sample estimate
12.5 acres · Maize · NPK Complex
Bags
37
Est. Cost
$1,332
Applications
3
Tell us about your field
Results update instantly as you adjust the inputs.
Recommended plan
Area
12.5 acres
Recommended Bags
95
50kg bags
Estimated Cost
$3,420
total for field
Application Schedule
Basal Application · At planting
Incorporate 38 bags into soil before or at sowing.
First Top Dress · 4–6 weeks after planting
Apply 33 bags at early vegetative stage.
Second Top Dress · 8–10 weeks after planting
Apply remaining 24 bags before flowering.
AI Recommendation
For maize targeting a standard yield of 2.4 tons/acre, NPK Complex (15-15-15) is sized to meet the crop's nitrogen requirement, which is the limiting nutrient for this blend — other nutrients may be over- or under-supplied since a single blend rarely matches a crop's ratio exactly. Soil test data would refine this estimate further; treat these figures as a starting point for planning, not a substitute for a lab-based nutrient plan.
How calculations work
A transparent, four-step process turns your field details into a fertilizer plan you can trust.
Tell us your field
Enter your crop, field area, and target yield. We support acres and hectares out of the box.
We model nutrient demand
Published N-P₂O₅-K₂O application rates for your crop combine with your chosen fertilizer's actual composition.
Get bags, cost, and schedule
See exactly how many bags to buy, what it costs, and when to apply each round.
Refine with AI guidance
A short recommendation highlights risks and adjustments worth considering for your plan.
Why farmers use it
Every input is designed to save time and money at the point where decisions actually get made.
Reduce waste
Right-size every application so nutrients feed your crop instead of running off into the soil.
Improve yields
Match fertilizer timing and volume to your target yield for consistent, healthier growth.
Estimate costs
Know your fertilizer spend before you buy, with a clear bag count and total cost breakdown.
Compare scenarios
Test different crops, fertilizers, and field sizes side by side to find your best plan.
Frequently asked questions
Everything you need to know before you start calculating.
The calculator uses published N-P₂O₅-K₂O application rates from agronomy extension guidance for each crop, scaled to your target yield and area. Real recommendations vary by soil test, variety, and region, so treat this as a solid planning starting point — not a replacement for a lab-based soil test.
You can switch between acres and hectares at any time using the toggle in the calculator. All outputs update instantly to match your selected unit.
Yes — simply change the crop or fertilizer type and the results recalculate immediately, so you can compare scenarios side by side before committing to a purchase.
Not yet. Soil composition, pH, and existing nutrient levels are the biggest drivers of real-world dosing. We're working on incorporating soil test data into future versions.
No account is required and nothing you enter is sent to a server — all calculations run locally in your browser.
It's a preview feature that surfaces short, contextual guidance based on your inputs. It's illustrative for now, with deeper AIFlare intelligence integration planned.
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