Handy tools
Fertilizer calculator
How many bags, how many spreader loads - and how many pounds of N, P₂O₅ and K₂O per acre actually go on? Enter your rate in lb per acre, the acres and the grade on the bag. Prefer kg/ha? Switch to metric.
For this field
6 tons12,000 lb of product
240240 bags of 50 lb
2spreader loads
- Nitrogen (N)
- 27 lb/ac · 2,160 lb in all
- Phosphorus (P)
- 69 lb/ac P₂O₅ · 5,520 lb in all (30 lb/ac as P)
- Potassium (K)
- 0 lb/ac K₂O · 0 lb in all (0 lb/ac as K)
- Sulfur (S)
- 0 lb/ac · 0 lb in all
- Rate in kg/ha
- 168.1 kg/ha
- Spreader loads
- 1 full load + 50% of a load
- Cost per acre
- Enter your price
- Cost for the field
- Enter your price
How we work it out
- Product: rate × acres. Bags and spreader loads = product ÷ bag or spreader size (rounded up to buy). A ton here is the US short ton of 2,000 lb.
- Nutrients: rate × the label %. So 150 lb/ac of 18-46-0 puts on 27 lb of N and 69 lb of P₂O₅ an acre - the “units” a soil-test recommendation asks for.
- P and K: US labels give phosphate (P₂O₅) and potash (K₂O). The element is P = P₂O₅ × 0.436 and K = K₂O × 0.830, so labels from any country compare fairly.
This does the arithmetic only - it doesn’t tell you what or how much to spread. A soil test and your county Extension office, certified crop adviser or agronomist are the best guide to rates; many states also have nutrient-management rules near water. We don’t show fertilizer prices; use what you pay. Nothing you type is stored or sent anywhere. For lb/ac ↔ kg/ha and other units use the farm unit converter.
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