{
    "name": "Fertiliser Application Rate Calculator",
    "url": "https://calculators.geekmidst.com/calculators/fertilizer-application-rate-calculator",
    "markdown": "https://calculators.geekmidst.com/calculators/fertilizer-application-rate-calculator.md",
    "category": "Agriculture",
    "description": "Convert a nutrient rate (kg/ha or lb/acre) into the amount of fertiliser product per hectare, per acre and for the whole field, with bag count.",
    "summary": "Fertiliser recommendations are given in nutrient; you buy product. Divide the nutrient rate by the product’s nutrient content to get the product rate.",
    "also_called": [
        "Fertilizer rate calculator",
        "Fertiliser product calculator"
    ],
    "applies_to": "Worldwide",
    "last_updated": "2026-10-29",
    "computation": "Results are computed in the visitor’s browser on the HTML page. This API describes the calculator; it does not compute results.",
    "inputs": [
        {
            "name": "nutrient_rate",
            "label": "Nutrient rate",
            "type": "number",
            "default": "100"
        },
        {
            "name": "rate_basis",
            "label": "Rate unit",
            "type": "select",
            "default": "kg_ha",
            "options": {
                "kg_ha": "kg per hectare",
                "kg_acre": "kg per acre",
                "lb_acre": "lb per acre"
            }
        },
        {
            "name": "nutrient_pct",
            "label": "Nutrient content of the product",
            "type": "number",
            "default": "46",
            "unit": "%"
        },
        {
            "name": "area",
            "label": "Field area",
            "type": "number",
            "default": "2"
        },
        {
            "name": "area_unit",
            "label": "Area in",
            "type": "segmented",
            "default": "ha",
            "options": {
                "acre": "Acres",
                "ha": "Hectares"
            }
        },
        {
            "name": "bag_kg",
            "label": "Bag size (optional)",
            "type": "number",
            "default": "45",
            "unit": "kg",
            "optional": true
        }
    ],
    "outputs": [
        {
            "key": "total_kg",
            "label": "Product for the field",
            "format": "number"
        },
        {
            "key": "product_kg_ha",
            "label": "Product per hectare",
            "format": "number"
        },
        {
            "key": "product_kg_acre",
            "label": "Product per acre",
            "format": "number"
        },
        {
            "key": "product_lb_acre",
            "label": "Product per acre (pounds)",
            "format": "number"
        },
        {
            "key": "nutrient_total_kg",
            "label": "Nutrient applied to the field",
            "format": "number"
        },
        {
            "key": "bags",
            "label": "Bags to buy",
            "format": "integer"
        }
    ],
    "formula": {
        "text": "Product rate = Nutrient rate ÷ (Nutrient % ÷ 100);  Product for field = Product rate × Area",
        "variables": {
            "Nutrient rate": "kg or lb of nutrient per unit area",
            "Nutrient %": "guaranteed analysis of the product"
        }
    },
    "worked_example": {
        "inputs": {
            "nutrient_rate": "100",
            "rate_basis": "kg_ha",
            "nutrient_pct": "46",
            "area": "2",
            "area_unit": "ha",
            "bag_kg": "45"
        },
        "steps": [
            "Product rate = 100 ÷ 0.46 = 217.39 kg/ha (87.98 kg/acre).",
            "For 2 ha: 217.39 × 2 = 434.78 kg, or 10 bags of 45 kg (9.66 rounded up)."
        ],
        "result": "To apply 100 kg N/ha as urea you need 217.4 kg urea per hectare: 434.8 kg, or 10 bags of 45 kg, for 2 ha."
    },
    "interpretation": "Use the product rate to set your spreader. If you split the dose, divide the product rate by the number of applications.",
    "assumptions": [
        "The nutrient percentage is the guaranteed analysis on the label."
    ],
    "limitations": [
        "Does not account for spreader overlap or losses; calibrate your spreader separately."
    ],
    "rules": null,
    "faqs": [
        {
            "question": "Is P on the label phosphorus or phosphate?",
            "answer": "Labels give P₂O₅ and K₂O. Make sure your recommendation is in the same form; P × 2.291 = P₂O₅ and K × 1.205 = K₂O."
        },
        {
            "question": "How do I convert lb/acre to kg/ha?",
            "answer": "Multiply by 1.121. For example, 100 lb/acre is about 112 kg/ha."
        }
    ],
    "sources": [],
    "related": [
        {
            "name": "Fertiliser NPK Calculator",
            "url": "https://calculators.geekmidst.com/calculators/fertilizer-npk-blend-calculator"
        },
        {
            "name": "Manure Application Rate Calculator",
            "url": "https://calculators.geekmidst.com/calculators/manure-application-rate-calculator"
        },
        {
            "name": "Seed Rate Calculator",
            "url": "https://calculators.geekmidst.com/calculators/seed-quantity-per-acre-calculator"
        }
    ],
    "disclaimer": null,
    "publisher": "GM¹X CalcVerse"
}