Fertilizer rate calculator (NPK)

PRO

Pounds of fertilizer to apply your target N rate.

Inputs

Result

Fertilizer per 1,000 sq ft
4.76 lb
Total fertilizer
4.8 lb
50 lb bags
1

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The formula

lb fertilizer per 1,000 sq ft = target N ÷ (%N ÷ 100).

Worked example

21-0-0 to deliver 1 lb N/K: 1 ÷ 0.21 = 4.76 lb per 1,000 sq ft.

Frequently asked

Typical N target?

0.5–1.0 lb N per 1,000 sq ft per feeding on lawns.