Home Spray Tip Calculator

Spray Tip Calculator: Nozzle Size, GPM & Color Guide

Calculate the required nozzle flow rate (GPM) for any target application rate, then match it to the correct spray tip size and ISO color code. Works for TeeJet, Hypro, John Deere, and all ISO-standard flat fan, air induction, and flood tips.

⚠️ Use this as a selection starting point.

The calculator uses the standard broadcast GPM formula and a 40 PSI capacity reference. Final nozzle choice, pressure range, droplet class, and pesticide compatibility must be verified with the specific nozzle manufacturer's chart and product label.

First time here? Use Tip Finder — enter GPA, speed, and spacing to get the right tip size in seconds.

On this page: Calculator · The formula explained · ISO color chart · Tip types guide · Pressure guide · Related tools · FAQ

Calculator

Spray Tip Size & Flow Rate Calculator

Choose a mode: Tip Finder to get required GPM and matching tip size · Flow Checker to verify a tip you already have · Speed Solver to find the speed needed for a given tip and GPA.

Enter your target application rate, ground speed, and nozzle spacing. The calculator finds the required GPM per nozzle and recommends the closest standard ISO tip size.

Tip: After finding your tip size, use the Sprayer Calibration Calculator to confirm your actual output in the field.

Already have tips installed? Enter the tip size (ISO number), your ground speed, and nozzle spacing to see what GPA you're actually applying — and whether it matches your target.

Know your tip size and target GPA? Find the exact ground speed required to hit that rate. Useful for dialing in existing equipment without changing tips.

⚠️ Changing speed affects application rate but also boom stability and coverage uniformity. Stay within the manufacturer's rated speed range for your tips.

Replacing or upgrading spray tips?

Once you've identified the right tip size above, here's what to look for:

See all recommended spray equipment including sprayers, measuring tools, and safety gear.

How to calculate spray tip size: the formula

The standard spray tip sizing formula relates gallons per acre (GPA), ground speed (mph), and nozzle spacing (inches) to the flow rate each nozzle must produce:

GPM = (GPA × MPH × Spacingin) ÷ 5,940

The 5,940 constant comes from unit conversion for broadcast spraying: (43,560 sq ft/acre × 12 in/ft) ÷ 88 ft/min per mph = 5,940. This is the standard US broadcast relationship used in nozzle-selection guidance.

Once you have the required GPM, match it to a standard ISO tip size at your operating pressure. Because tip flow rate scales with the square root of pressure:

GPMactual = GPMrated × √(PSIactual ÷ 40)

This page uses 40 PSI (2.76 bar) as the reference capacity point for the color/size lookup. Actual pressure ranges and droplet classifications vary by nozzle family, so use the manufacturer's chart for final selection.

Example: What tip size for 15 GPA at 12 mph with 20-inch spacing?

Required GPM = (15 × 12 × 20) ÷ 5,940 = 0.606 GPM. At 40 PSI, the closest standard tip is a 06 (White) at 0.6 GPM, or a 05 (Gray) at 0.5 GPM run at slightly reduced speed. Use the Tip Finder tab to explore different speed and spacing combinations instantly.

ISO-size spray tip color chart: common capacity colors

The color sequence below follows the common ISO-size capacity colors used by major agricultural nozzle manufacturers. For example, Pentair Hypro lists 015 Green, 02 Yellow, 025 Lilac, 03 Blue, 04 Red, 05 Brown, 06 Gray, and 08 White on its ULD nozzle line.

Tip sizeColorReference GPM @ 40 PSIGPM @ 30 PSIGPM @ 20 PSI
01Orange0.100.0870.071
015Green0.150.1300.106
02Yellow0.200.1730.141
025Lilac0.250.2170.177
03Blue0.300.2600.212
04Red0.400.3460.283
05Brown0.500.4330.354
06Gray0.600.5200.424
08White0.800.6930.566
10Light Blue1.000.8660.707

Flow at another pressure is estimated with GPM₂ = GPM₁ × √(PSI₂ ÷ PSI₁). Verify the actual nozzle family: Pentair Hypro ULD specifications and TeeJet spray-tip catalog.

Spray nozzle tip types: size and type are separate choices

Tip size controls nominal flow capacity. Tip family/type controls characteristics such as spray angle, pressure range, and droplet spectrum. A 04 tip is not automatically the same application choice across flat-fan, air-induction, twin-fan, or flood families even when the capacity code is the same.

As one manufacturer example, Pentair Hypro lists its ULD air-induction nozzle family at 20–115 PSI, showing why a single “best PSI” rule should not be applied to every nozzle. For regulated pesticide applications, the product label's nozzle, droplet, and pressure requirements take priority.

Operating pressure: use the nozzle-family chart

Increasing pressure raises nozzle flow approximately with the square root of the pressure ratio, but droplet size, spray angle, pattern quality, and allowed pressure range are nozzle-specific. There is no universal 30–40 PSI “optimum” that applies to every flat fan, air-induction, flood, or cone nozzle.

Reference flow20 PSI30 PSI40 PSI60 PSI
0.20 GPM @ 40 PSI0.1410.1730.2000.245
0.30 GPM @ 40 PSI0.2120.2600.3000.367
0.40 GPM @ 40 PSI0.2830.3460.4000.490

Use the calculator for flow math, then verify pressure range and droplet class in the specific manufacturer's chart and pesticide label before application.

Frequently asked questions

How do I calculate the correct spray tip size?

Use GPM = (GPA × MPH × nozzle spacing in inches) ÷ 5,940 to calculate required flow per nozzle. Then use the specific nozzle manufacturer's table to choose a capacity and pressure that meet the target flow and the required droplet/application criteria.

What do TeeJet and Hypro spray tip color codes mean?

Major agricultural nozzle makers use ISO-size capacity colors to identify nominal nozzle sizes. Common examples include 015 Green, 02 Yellow, 025 Lilac, 03 Blue, 04 Red, 05 Brown, 06 Gray, and 08 White. This page uses 40 PSI as a reference flow point; verify the specific nozzle family because pressure range and droplet class vary.

Is a TeeJet 03 the same as a Hypro 03?

A 03 capacity code is intended to identify the same nominal flow size, and both TeeJet and Hypro use Blue for 03 in their common agricultural color coding. That does not make the nozzle families interchangeable for every application: spray angle, body/cap compatibility, pressure range, and droplet spectrum can differ.

What is the difference between a John Deere spray tip and a TeeJet?

Nozzle capacity codes can follow common industry sizing conventions, but brand, nozzle family, cap/body compatibility, spray angle, pressure range, and droplet spectrum still matter. Do not assume physical interchangeability from the color or capacity number alone; verify the equipment and nozzle manufacturer specifications.

How do I quickly calculate what a 10% change in speed does to my GPA?

GPA and speed have an inverse relationship — if you increase speed by 10%, your GPA drops by approximately 9% (since GPA = constant ÷ speed). So going from 10 mph to 11 mph while applying 15 GPA would drop output to about 13.6 GPA. Use the Speed Solver tab to find the exact speed needed for any target GPA without changing tips.

What tip size should I use for herbicide applications?

Calculate the required GPM from your target GPA, speed, and nozzle spacing, then choose a nozzle family and capacity that meet the specific herbicide label requirements for carrier volume, droplet class, nozzle type, and pressure. There is no universal 02–04 tip range that is correct for every herbicide.

What pressure should I run flat fan spray tips?

Use the pressure range published for the exact nozzle family. Pressure affects both flow and droplet behavior, and different flat-fan and air-induction designs can have very different approved operating ranges. This calculator can estimate flow at pressure, but the manufacturer's pressure/droplet chart controls final selection.

How do I know when spray tips need replacing?

Catch-test nozzle output at a known pressure and compare it with the manufacturer's new-nozzle specification and the average across the boom. Replace worn, damaged, distorted, or out-of-tolerance tips according to the manufacturer's guidance. Do not rely on a universal operating-hours replacement interval.

What tip size is close to 15 GPA at 15 mph with 15-inch spacing?

Required flow is (15 × 15 × 15) ÷ 5,940 = 0.568 GPM per nozzle. At a 40 PSI reference point, a 06 capacity (0.60 GPM) is the nearest common size in this chart. Verify the exact nozzle family, operating pressure, droplet requirement, and manufacturer chart before selecting it.