SprayMaster, the spray tank mix calculator for applicators

What can you calculate?

The app is a set of focused calculators, each doing one job from numbers you already have: the label rate, your tank and your sprayer.

• Tank Mix (free): product per tank from a rate stated Per Acre, Per 1,000 ft² or Per Gallon (metric: Per Hectare, Per 100 m², Per Litre), the land one tank covers, and, for a whole job, total product and the number of tank loads.
• Mix Ratio (free): dilution for handheld and backpack sprayers, product per gallon or litre times tank size, with the Percent Solution when the product is in fl oz or mL.
• Sprayer Calibration (Pro): gallons per acre or L/ha from nozzle output, ground speed and spacing (Nozzle & Speed), or by the catch method (1/128 Acre in US units, Measured Run in metric).
• Rate Converter (Pro): nine two-way conversions, such as lb/acre to oz/1,000 ft², percent to fl oz/gal and GPA to L/ha.
• Area / Acreage (Pro): acres or hectares of a Rectangle, Circle / Pivot or Triangle from dimensions you measured.
• History (free): tap Save on any calculator to keep the result with date and time.

Quick start: your first tank

1. Open Tank Mix from the Calculators section of the home list.
2. Set Units to US or Metric. The choice sticks on every screen and at next launch.
3. Type the Label Rate from the label, pick the Product Unit the label uses and the Rate Basis, for example Per Acre.
4. Under Your Sprayer, enter Tank Size and your calibrated Application Rate in GPA or L/ha.
5. Read Product per Tank and Covers per Tank in the Mix section, then tap Save if you want it in History.

Example: a label rate of 32 fl oz per acre, a 100 gal tank, a sprayer calibrated at 20 GPA. 160 fl oz per tank, 5 acres covered. Turn on Size a whole job, type 40 acres, and you get 1,280 fl oz across 8 tank loads.

Free, or with SprayMaster Pro

SprayMaster is free to download. Tank Mix, Mix Ratio, the US / metric switch and History are free for everyone, with a banner on the home list and a full-screen ad every third time you open Tank Mix or Mix Ratio.

SprayMaster Pro turns on Sprayer Calibration, Rate Converter and Area / Acreage, and removes every ad. Pick a Weekly or Yearly subscription, or pay once for Lifetime — all three give you the same three calculators, so pick by how long you'll be spraying this season rather than by price alone.

Privacy, offline use and permissions

Every calculation runs on your iPhone, so the app works in a field with no signal. A connection is only used for ads in the free version and to buy or restore Pro. There is no account.

Saved results stay on the phone. The only permission it asks for is Apple's tracking prompt, and that's only about ads. Say no and nothing in the calculators changes — ads just stop being personalized. No camera, location, microphone, contacts, notifications.

What it does not do

• It ships no product rates and recommends no products: you type the rate from the label in front of you.
• It does not convert product units inside Tank Mix: a rate in pints comes out in pints.
• Calibration covers broadcast boom nozzles only: no banded spraying, airblast, granular spreaders, pressure or nozzle-tip charts, and no built-in stopwatch.
• No GPS or map measuring, no export or sharing of History, no iCloud sync.
• iPhone only, portrait, iOS 17 or later. There is no iPad, Apple Watch or Android version.