Farming & agriculture
Fertiliser NPK quantities Calculator
Calculate delivered labelled nutrients and product order quantities. This free fertiliser npk quantities calculator shows the calculation and its assumptions so you can compare your own figures.
Your results
Calculate delivered labelled nutrients and product order quantities.
Calculated outcomes
- Phosphate P2 O5 Kg Ha
- 15 kg/ha
- Potash K2 OKg Ha
- 30 kg/ha
- Bags
- 50
- Product Cost
- €1,500.00
Assumptions and estimates
- Method: Each labelled nutrient = product rate × label fraction. Product order = kg/ha × area; bag count rounds up.
- Label phosphate and potash are P₂O₅ and K₂O, not elemental P and K. This does not assess crop requirement, nutrient limits, soil tests or legal application conditions.
Useful next steps
- Use Compare options to test an alternative side by side.
- Copy, print or download a record of this calculation when you need one.
Reports open your email app addressed to s@s1.ie with the public page address only. Your inputs are never added.
How the fertiliser npk quantities calculation works
Each labelled nutrient = product rate × label fraction. Product order = kg/ha × area; bag count rounds up.
Label phosphate and potash are P₂O₅ and K₂O, not elemental P and K. This does not assess crop requirement, nutrient limits, soil tests or legal application conditions.
Using this calculator
- Enter your own figures in the labelled inputs. Keep the currencies, units and time periods consistent.
- Choose any applicable rate profile, pattern or assumption shown for this tool. Open additional inputs when relevant.
- Review nitrogen kg ha and total product kg, then read the stated assumptions and eligibility conditions before using the result.
Worked example
This is a static example using illustrative inputs, not facts about you or today’s date. The displayed eligibility selections and assumptions apply only to this example.
See example inputs
- Product application (kg/ha)
- 250
- Label nitrogen N (%)
- 18
- Label phosphate P₂O₅ (%)
- 6
- Label potash K₂O (%)
- 12
- Area (ha)
- 10
- Bag weight (kg)
- 50
- Product price (€/tonne)
- 600
- Nitrogen Kg Ha
- 45 kg/ha
- Total Product Kg
- 2,500 kg