Comparison
DAP vs MAP: comparing two phosphate fertilizers
Last updated July 22, 2026
Short answer
What the numbers mean
The grade is the percent by weight of N-P2O5-K2O. Both products supply phosphate plus some nitrogen; neither carries potassium.
| Product | Grade | lb P₂O₅ / ton | lb N / ton | Reaction around the granule |
|---|---|---|---|---|
| DAP (diammonium phosphate) | 18-46-0 | 920 | 360 | Alkaline (basic) zone |
| MAP (monoammonium phosphate) | 11-52-0 | 1,040 | 220 | Acidic zone |
How to compare them on price
Put both on cost per pound of phosphate, using the delivered price:
cost per lb P₂O₅ = delivered price per ton ÷ lb P₂O₅ per tonIllustrative delivered prices — not quoted prices:
| Product | Delivered price | lb P₂O₅ / ton | Cost per lb P₂O₅ |
|---|---|---|---|
| DAP (18-46-0) | $760 / ton | 920 | $0.83 |
| MAP (11-52-0) | $800 / ton | 1,040 | $0.77 |
Also value the nitrogen you get with each: at these grades a ton of DAP carries 360 lb of N versus 220 lb for MAP. If you would otherwise buy that nitrogen separately, credit it when you compare.
Does the pH difference matter?
MAP creates a more acidic zone around each granule and DAP a more basic one. In theory that can favor MAP on high-pH (calcareous) soils, but University of Minnesota Extension reports that agronomic and economic data show no crop-yield differences between the two, and advises choosing on nutrient content, price, and availability. For most growers, price and supply — not chemistry — decide.
What this comparison does not decide
How much phosphate to apply, whether you need it at all, and how to place it are agronomic questions that depend on a soil test and your crop. This page only helps you compare the two products on cost.
Price comparison, not agronomic advice
This page helps you compare fertilizer prices on the same basis. It does not recommend application rates or products for your field. Rates and nutrient decisions depend on a soil test, your crop and growth stage, and local guidance from a qualified agronomist. See our Terms.
Sources
- Understanding phosphorus fertilizersUniversity of Minnesota Extension · Reviewed 2018 · Accessed July 22, 2026
- Phosphorus fertilizer sources: What are the differences?University of Minnesota Extension · October 2023 · Accessed July 22, 2026
Keep reading
Weighing DAP against MAP quotes? FertaFind compares them on delivered cost per pound of phosphate.
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