Drip Irrigation Design Calculator

Calculate emitter count, system flow rate, zone sizing, and daily run time for drip irrigation systems.

Inputs

Field area (acres)

Row spacing (ft)

Plant spacing (ft)

Emitters per plant

Emitter flow rate (GPH)

Peak crop ET (in/day)

Available flow (GPM)

Tab to move between fields

Results

Total plants

2,904

Daily run time (hrs)

2.2

Total emitters5,808

System flow (GPM)48.4

Zones needed4

Flow per zone (GPM)12.1

Daily water use (gal)6,398

How to Use This Calculator

Enter your field area in acres and row and plant spacing in feet.
Set emitters per plant and emitter flow rate in GPH for your chosen emitter type.
Enter peak crop ET in inches per day and available water source flow in GPM.
Review Total emitters, System flow (GPM), and Zones needed to size your infrastructure.
Use Daily run time (hrs) to program your irrigation controller for peak-season demand.

How the result changes with Row spacing (ft)

Row spacing (ft)	Total plants	Daily run time (hrs)
10	1,452	2.2
35	415	2.2
65	223	2.2
90	161	2.2

What each input means

Field area (acres): Total irrigated area in acres.
Row spacing (ft): Distance between crop rows in feet.
Plant spacing (ft): Distance between plants within a row in feet.
Emitters per plant: Number of drip emitters serving each plant.
Emitter flow rate (GPH): Flow rate of each emitter in gallons per hour. Typical: 0.5-2 GPH.
Peak crop ET (in/day): Peak daily crop evapotranspiration. Typical: 0.15-0.35 in/day.
Available flow (GPM): Maximum flow rate available from your water source.

What each result means

Total plants: Estimated plant count based on spacing and field size.
Total emitters: Total number of drip emitters needed.
System flow (GPM): Total system flow rate in gallons per minute.
Daily run time (hrs): Hours per day to run system to meet peak ET demand.
Zones needed: Minimum irrigation zones based on available flow.
Flow per zone (GPM): Flow rate per zone when evenly divided.
Daily water use (gal): Total daily water consumption at peak ET.

How this is calculated

Worked example, using the default values

Identify Input Parameters
4 parameters
Field area (acres) = 1, Row spacing (ft) = 5, Plant spacing (ft) = 3, Emitters per plant = 2 = 7 input(s) provided
Calculate Total plants
Total plants = plantsPerAcre * fieldAcres
2904 = 2904
Calculate Daily run time
Daily run time = dailyWaterPerPlant / (emitterFlowRate * emittersPerPlant)
2.2 = 2.2
Calculate Total emitters
Total emitters = totalPlants * emittersPerPlant
5808 = 5808
Calculate System flow
System flow = totalFlowGPH / 60
48.4 = 48.4

The questions that sit next to this one — chosen by subject, including calculators filed under a different category.

Irrigation

Sprinkler System Design Calculator

Calculate precipitation rate, head count, zone sizing, and run times for sprinkler irrigation systems.

Precision Irrigation

Subsurface Drip Design Calculator

Design SDI lateral layout from crop spacing, emitter specs, and peak ET to determine tape length, flow rates, and run times.

Greenhouse

Greenhouse Irrigation System Calculator

Size a drip or overhead irrigation system for greenhouse benches including emitter count, flow rate, and water usage.

Landscaping

Irrigation Zone Calculator

Calculate the number of sprinkler heads, flow rate, run time, and pipe size for an irrigation zone.

Garden Planning

Irrigation Schedule Calculator

Plan your garden watering schedule based on plant type, soil, climate, and sun exposure. Get gallons per week, session duration, and cost estimates.