What do the numbers mean?

N-P-K percentages: nitrogen for leaves, phosphorus for roots/flowers, potassium for health.

Lbs needed = (desired nutrient lbs × 100) / % in fertilizer.

NPK Amount Calculator

Calculate the actual weight of Nitrogen (N), Phosphorus (P), and Potassium (K) in a bag of fertilizer based on its NPK ratio.

Find out the actual weight of Nitrogen (N), Phosphorus (P), and Potassium (K) in your bag of fertilizer.

Total Fertilizer Weight (lbs)

N (%)

P (%)

K (%)

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