Fertilizer Calculator
Calculate the exact fertilizer dose for your crop, field size, and soil type. Supports 25+ crops (rice, wheat, sugarcane, potato, tomato, cotton and more), 20+ fertilizers (Urea, DAP, MOP, SSP, NPK complexes), Indian area units (bigha, guntha, kattha, dismil), split application schedule, and cost optimizer.
4 Fertilizer Combinations
DAP + Urea + MOP
Standard recommendation using DAP for phosphorus. Most widely used combination across India.
| Fertilizer | per ha | Total | Cost |
|---|---|---|---|
| DAP | 130.4 kg | 130.4 kg | ₹3,522 |
| Urea | 209.8 kg | 209.8 kg | ₹1,364 |
| MOP | 66.7 kg | 66.7 kg | ₹1,133 |
| Total | 406.9 kg | 406.9 kg | ₹6,019 |
SSP + Urea + MOP
SSP also supplies 11% sulphur and 19% calcium. Ideal for oilseeds, pulses, and sulphur-deficient soils.
| Fertilizer | per ha | Total | Cost |
|---|---|---|---|
| SSP | 375.0 kg | 375.0 kg | ₹2,625 |
| Urea | 260.9 kg | 260.9 kg | ₹1,696 |
| MOP | 66.7 kg | 66.7 kg | ₹1,133 |
| Total | 702.5 kg | 702.5 kg | ₹5,454 |
10-26-26 Complex + Urea
Single complex fertilizer for basal application; reduces number of bags and labour.
| Fertilizer | per ha | Total | Cost |
|---|---|---|---|
| 10-26-26 | 153.8 kg | 153.8 kg | ₹4,308 |
| Urea | 227.4 kg | 227.4 kg | ₹1,478 |
| SSP | 125.0 kg | 125.0 kg | ₹875 |
| Total | 506.3 kg | 506.3 kg | ₹6,661 |
17-17-17 + Top-dress Urea
Balanced complex fertilizer. Good where N, P, K deficiencies are equal.
| Fertilizer | per ha | Total | Cost |
|---|---|---|---|
| 17-17-17 | 235.3 kg | 235.3 kg | ₹5,882 |
| Urea | 173.9 kg | 173.9 kg | ₹1,130 |
| SSP | 125.0 kg | 125.0 kg | ₹875 |
| Total | 534.2 kg | 534.2 kg | ₹7,888 |
Cost Comparison
How to Use This Fertilizer Calculator
NPK Calculator
Enter N, P, K requirements (kg/ha) and field area. Get 4 fertilizer combinations side-by-side with cost comparison.
Crop Calculator
Select your crop (rice, wheat, maize, potato...) and soil fertility. NPK is auto-filled from ICAR data. Get split application schedule.
Blend Analyzer
Add any mix of fertilizers with quantities. See total N, P, K contributed and cost per hectare.
Cost Optimizer
Enter current fertilizer prices in your area. Calculator ranks all combinations from cheapest to most expensive.
Unit Converter
Convert area (hectare, acre, bigha, guntha, kattha) and nutrient rates (kg/ha, kg/acre, lbs/acre) instantly.
Print / Copy
Use the Copy or Print button to save your fertilizer recommendation for field use.
Fertilizer Calculation Formula (NPK Method)
The standard method to calculate fertilizer quantity from nutrient requirements:
ICAR-Recommended NPK Doses for Major Crops
Standard fertilizer recommendations from the Indian Council of Agricultural Research (ICAR) for medium fertility soils. Adjust up by 20-25% for low fertility soils and down by 15-20% for high fertility or soil test-based recommendations.
| Crop | N (kg/ha) | P₂O₅ (kg/ha) | K₂O (kg/ha) |
|---|---|---|---|
| Rice (Paddy) | 120 | 60 | 40 |
| Wheat | 120 | 60 | 40 |
| Maize (Corn) | 150 | 75 | 50 |
| Sugarcane | 250 | 100 | 120 |
| Cotton | 150 | 75 | 75 |
| Potato | 180 | 100 | 120 |
| Tomato | 150 | 100 | 100 |
| Mustard | 100 | 50 | 40 |
| Soybean | 30 | 60 | 40 |
| Banana | 200 | 60 | 200 |
| Chickpea (Chana) | 25 | 50 | 25 |
| Groundnut | 25 | 50 | 50 |
Common Fertilizer NPK Reference
| Fertilizer | N-P-K (%) | Price (approx) | Notes |
|---|---|---|---|
| Urea | 46-0-0 | ₹6.5/kg | 46 kg N per 100 kg |
| DAP | 18-46-0 | ₹27/kg | 46 kg P₂O₅ per 100 kg |
| MOP | 0-0-60 | ₹17/kg | 60 kg K₂O per 100 kg |
| SSP | 0-16-0 | ₹7/kg | +11% S, +19% Ca |
| 10-26-26 | 10-26-26 | ₹28/kg | Complex NPK |
| 17-17-17 | 17-17-17 | ₹25/kg | Balanced complex |
Indian Area Unit Conversion Guide
Fertilizer recommendations are published per hectare, but farmers in India commonly measure land in local units. Our calculator supports all regional variants:
| Unit | Region | = Hectares | = Acres | Urea for Rice (120N) |
|---|---|---|---|---|
| 1 Bigha | UP / Rajasthan | 0.2529 | 0.625 | 55 kg |
| 1 Bigha | MP / CG | 0.3307 | 0.817 | 71 kg |
| 1 Bigha | West Bengal | 0.1338 | 0.330 | 29 kg |
| 1 Guntha | Maharashtra | 0.0101 | 0.025 | 2.2 kg |
| 1 Kattha | Bihar / UP | 0.0134 | 0.033 | 2.9 kg |
| 1 Dismil | Bihar / WB | 0.0405 | 0.100 | 8.7 kg |
| 1 Cent | South India | 0.0040 | 0.010 | 0.9 kg |
| 1 Acre | All India | 0.4047 | 1.000 | 87 kg |
Frequently Asked Questions
How do I calculate fertilizer dose per hectare?
To calculate fertilizer per hectare: 1) Determine the nutrient requirement (e.g., Rice needs 120 kg N, 60 kg P₂O₅, 40 kg K₂O per ha). 2) For Urea (46% N): Urea = 120/0.46 = 261 kg/ha. 3) For DAP (18% N, 46% P₂O₅): DAP = 60/0.46 = 130 kg/ha (also provides 130 × 0.18 = 23.4 kg N). 4) Remaining N from Urea = (120-23.4)/0.46 = 209 kg/ha. 5) For MOP (60% K₂O): MOP = 40/0.60 = 67 kg/ha. Our calculator does all this automatically for 25+ crops.
How much Urea is needed per acre for wheat?
Wheat typically needs 120 kg N per hectare (medium fertility soil). 1 hectare = 2.47 acres, so that is 120/2.47 = 48.6 kg N per acre. Urea (46% N) needed = 48.6/0.46 = 105.6 kg Urea per acre. This is usually split: 50% at sowing + 25% at first irrigation + 25% at second irrigation. Use the Crop Calculator tab above, select Wheat, enter area in acres, and the split schedule is generated automatically.
How is DAP fertilizer dose calculated?
DAP (Di-ammonium Phosphate) contains 18% N and 46% P₂O₅. To meet a phosphorus requirement: DAP (kg/ha) = P₂O₅ required (kg/ha) ÷ 0.46. Example: Need 60 kg/ha P₂O₅ → 60/0.46 = 130 kg DAP/ha. DAP also contributes 130 × 0.18 = 23.4 kg N, which reduces the Urea needed. Full formula is handled in the NPK Calculator tab.
What are N-P-K numbers on fertilizer bags?
The three numbers (e.g., 46-0-0, 18-46-0, 0-0-60) represent the percentage by weight of: N = Nitrogen (promotes leafy growth), P = Phosphorus as P₂O₅ (promotes root development, flowering), K = Potassium as K₂O (promotes disease resistance, fruit quality). A 50 kg bag of Urea (46-0-0) contains 50 × 0.46 = 23 kg of actual nitrogen.
What is the fertilizer calculation formula?
The universal formula is: Fertilizer quantity (kg) = Nutrient required (kg) ÷ Nutrient content (%). For compound fertilizers: Calculate the limiting nutrient (usually P or K from complex fertilizer), apply that, then top-up N with Urea. Example for DAP route: DAP (kg/ha) = P/0.46; N from DAP = DAP × 0.18; Extra Urea = (N required – N from DAP)/0.46; MOP (kg/ha) = K/0.60.
How to convert fertilizer per hectare to per acre?
1 hectare = 2.47105 acres, so divide by 2.47 to convert kg/ha to kg/acre. Multiply by 2.47 to convert kg/acre to kg/ha. Example: 261 kg Urea/ha = 261/2.47 = 105.7 kg Urea/acre. To convert to lbs/acre: multiply kg/acre by 2.205. Use the Unit Converter tab for quick conversions between all Indian and international area units.
How much fertilizer per bigha of land?
Bigha varies by region: 1 Bigha (UP/Rajasthan) = 0.2529 ha, 1 Bigha (MP/CG) = 0.3307 ha, 1 Bigha (WB) = 0.1338 ha. Select your regional bigha in the area unit dropdown. Example: Rice needing 261 kg Urea/ha → 261 × 0.2529 = 66 kg Urea per bigha (UP). The calculator handles all regional bigha variants automatically.
What is the difference between DAP route and SSP route fertilizer?
DAP route: Uses DAP (18-46-0) for phosphorus + Urea (46-0-0) for nitrogen + MOP (0-0-60) for potassium. DAP is concentrated (46% P), fewer bags needed. SSP route: Uses SSP (0-16-0) for phosphorus + Urea for N + MOP for K. SSP has only 16% P so more bags are needed BUT SSP also provides 11% Sulphur and 19% Calcium — making it ideal for oilseeds (mustard, groundnut), pulses, and sulphur-deficient soils. The cost optimizer tab compares both routes for your inputs.
How much fertilizer is needed for rice per hectare?
ICAR recommendation for paddy rice: 120 kg N + 60 kg P₂O₅ + 40 kg K₂O per hectare under medium soil fertility. Using DAP route: DAP = 130 kg/ha, Urea = 209 kg/ha, MOP = 67 kg/ha. Total: 406 kg fertilizer per hectare. Split: Full DAP + MOP at transplanting, 50% Urea at transplanting, 25% Urea at tillering, 25% Urea at panicle initiation.
Can I use this calculator for lawn fertilizer in the US?
Yes — the NPK Calculator tab accepts any N, P, K values and any area unit (sq ft, acre, sq meter, hectare). For US lawn fertilizer: Select 'sq ft' or 'acre', enter N/P/K needs in kg/ha (convert your lbs/1000 sqft × 100 to get kg/ha), and pick any fertilizer combination. The Unit Converter tab also helps convert between kg/ha, kg/acre, and lbs/acre.
What is the NPK requirement for wheat?
Standard wheat NPK (medium fertility): 120-60-40 kg/ha (N-P₂O₅-K₂O). High-yielding varieties: 150-60-40 kg/ha. Low fertility soils: 90-60-40 kg/ha. Application: At sowing — all P+K (as DAP+MOP) + 50% N (as Urea). At first irrigation (21 DAS) — 25% N. At second irrigation (42 DAS) — 25% N. Our Crop Calculator auto-fills wheat NPK and generates the split schedule.
How much fertilizer per kattha / guntha / dismil?
These are common Indian area units: 1 Kattha = 0.013378 ha (approx 1/75 acre), 1 Guntha = 0.010117 ha (1/40 acre), 1 Dismil = 0.040468 ha (1/100 acre), 1 Cent = 0.004047 ha (1/100 acre). Select your unit in the area dropdown and the calculator converts automatically. For 5 katthas of wheat needing 261 kg Urea/ha: 261 × 5 × 0.013378 = 17.5 kg Urea.
How does the fertilizer cost optimizer work?
The Cost Optimizer tab compares all available fertilizer combinations side-by-side for your N, P, K requirements. You can enter current local prices (₹/kg) for each fertilizer — the calculator ranks all combinations from cheapest to most expensive for your field area. SSP route is often cheapest for sulphur-rich soils; DAP route is most popular. The cheapest option is highlighted in green.
What is the fertilizer split application schedule?
Split application means dividing the total fertilizer into multiple doses applied at different crop growth stages. Example for Rice: Basal (at transplanting) — 100% P, 100% K, 50% N. Tillering (21-25 DAT) — 25% N. Panicle initiation (45-50 DAT) — 25% N. Splitting nitrogen reduces losses due to volatilization and leaching, and increases nutrient use efficiency by 15-30%. The Crop Calculator generates exact split quantities per application.
Is Urea or DAP better for rice?
Both are used together. DAP provides phosphorus (P) — essential for root development and tillering in rice. Urea provides the bulk of nitrogen (N) — for vegetative growth and grain filling. The most common combination for rice is: DAP 130 kg/ha (basal) + Urea 209 kg/ha (split 3 times) + MOP 67 kg/ha (basal). DAP alone cannot supply enough N for rice.
How to calculate fertilizer for 1 acre of sugarcane?
Sugarcane has high NPK requirements: 250-100-120 kg/ha (N-P₂O₅-K₂O). For 1 acre = 0.4047 ha: N = 250×0.4047 = 101 kg, P = 100×0.4047 = 40 kg, K = 120×0.4047 = 49 kg. DAP route: DAP = 40/0.46 = 87 kg, Urea = (101-87×0.18)/0.46 = 185 kg, MOP = 49/0.60 = 82 kg. Select Sugarcane in Crop Calculator with area = 1 acre for automatic calculation.