Irrigation Calculator

📌 Start here. Almost every other calculator (heads, flow, pipe size, valve size, run time) builds off a zone's area. Name and add each hydrozone below — front yard, back yard, flower bed, parking lot strip, etc. — then pick the one you're working on from a "Load Zone" dropdown elsewhere to carry it forward.

Zone Area

Zone Name

Shape

Length (ft)

Width (ft)

Head Spacing & Count

Load Zone

Zone Area (sq ft)

Head Spacing / Radius (ft)

Layout Pattern

Precipitation Rate

Head-to-head spacing, spray/rotor zones

Flow per Head (GPM)

Spacing A (ft)

Spacing B (ft)

Nozzle Flow (GPM / PSI)

Flow scales with the square root of pressure

Rated Flow (GPM)

Rated Pressure (PSI)

Actual/Available Pressure (PSI)

Zone Flow / Total GPM

Number of Heads

Flow per Head (GPM)

Pipe Sizing

Flow (GPM)

Max Velocity (ft/sec)

Friction Loss

Hazen-Williams, PVC C=150 default

Flow (GPM)

Pipe Diameter (in, actual ID)

Pipe Length (ft)

C-Factor

Valve / Manifold Sizing

Zone Flow (GPM)

Wire Sizing

24VAC solenoid wire run, copper, 2-wire path

One-Way Distance (ft)

Total Current Draw (A)

System Voltage (VAC)

Max Allowed Drop (V)

Backflow Preventer Sizing

System / Point-of-Connection Flow (GPM)

Drip Emitters

Number of Plants

Emitters per Plant

Emitter Flow (GPH each)

Zone Run Time

Zone Type

Target Water Depth (inches)

Precipitation Rate (in/hr)

0

Materials List

Zone

Material Description

Quantity

Unit Cost ($)

Waste Factor (%)

Labor Estimator

Hourly Rate ($)

Crew Size

Total Hours

Bid & Estimate

Tip: Values from Materials & Labor calculators will auto-populate below.

Material Cost ($)

Labor Cost ($)

Miscellaneous ($)

Overhead ($)

Markup (%)