Sprinkler Coverage Calculator

Estimate the number of sprinkler heads needed to cover an area with the desired overlap.

Sprinkler Heads
— heads
Rounded up.

Usage Tip

Aim for head-to-head coverage, where each head’s spray reaches the next head; it is the most even way to avoid dry spots.

THE MATH
effective radius = radius × (1 − overlap ÷ 100)
coverage per head = π × effective radius²
heads = round up( area ÷ coverage per head )
Each spray head waters a circle, but heads must overlap so there are no dry gaps. The effective radius shrinks by the overlap, and head count is the area over each head coverage.
Enter the area, the spray radius, and the overlap percentage (head-to-head spacing usually means about 30 to 50 percent).
Head count rounds up.
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