Drip Irrigation Calculator

How much drip tubing do I need?

ft
ft
in
in
gph
in

Order this much drip tubing

84feet

Tubing includes one header across the bed. Check your tubing chart for the maximum run at your pressure, and use 1 GPH emitters on clay or 2 GPH on sand as a starting point.

20 ft4 ft4 lines, emitters every 12 in
Lines4
Emitters84
Zone flow75.6 gph
Run time40 min for 1 in

Lay out drip lines for a bed and see tubing, emitters, zone flow and run time before you buy parts.

How it works

Lines = bed width ÷ line spacing, tubing = lines × length plus one header. Emitters = lines × (length ÷ emitter spacing + 1). Run time is gallons ÷ zone flow.

Before you order

  • Clay spreads water wide, so emitters can sit further apart. Sand needs them closer.
  • Keep the total zone flow under what your tubing and valve are rated for.
  • Add a pressure regulator and filter, since drip runs at much lower pressure than a hose.

Common questions

How far apart should drip emitters be?

Often 12 to 18 inches, closer in sandy soil. Tubing with built-in emitters comes in both.

How long should drip irrigation run?

It depends on emitter flow and bed size, which is why this page calculates it from your numbers.