Sprinkler Coverage Calculator
Heads Needed
Calculate how many sprinkler heads you need
Watering Time
Calculate how long to run sprinklers
Formula
Heads = Area / (Spacing²) | Run Time (min) = Target Inches / Precipitation Rate × 60 / Days per Week
Frequently Asked Questions
How far apart should sprinkler heads be?
Use head-to-head spacing where each sprinkler's throw reaches the next head. For a 25-foot radius rotor, space heads 25 feet apart. This provides the 50% overlap needed for uniform coverage.
How long should I run my sprinklers?
Most lawns need 1-1.5 inches of water per week. With a typical spray head precipitation rate of 1.5 in/hr, run for about 20 minutes per session, 3 times per week. Place a tuna can on the lawn to measure actual output.
How many GPM do I need for sprinklers?
Spray heads use 1-3 GPM each, rotors use 2-8 GPM. A typical zone has 4-8 heads. Design zones so total GPM does not exceed your water supply (usually 8-15 GPM for residential). Use a flow test at your hose bib to measure.
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