Pesticide Spray Calculator

Calculate exact tank mix amounts. From label rate to bucket. Backpack, ATV, and tractor sprayer sizing. Conversion across all common units.

Mix calculation

Application

Area to spray

Area unit acres 1,000 sq ft sq ft hectares

Label rate

Rate unit lb / acre oz / acre qt / acre oz / 1000 sq ft oz / gal water (mix rate) mL / gal water % solution

Sprayer

Sprayer type Backpack (4 gal) ATV / 25 gal Tractor 100 gal Tractor 300 gal Custom volume

Tank volume (gal)

Water rate (gal/acre) Hydraulic 15-30; airblast 50-100; backpack 30-60

Sprayer water volume reference

Sprayer / situation	Water rate (gal/acre)
Backpack hand sprayer	30-60 (high; thorough coverage)
Boom sprayer (low pressure)	15-25
Boom sprayer (high pressure)	20-40
Airblast (orchards)	50-150 (canopy spray)
Aerial	1-5 (very low; concentrated)
Dripline (chemigation)	Variable; typically diluted into normal irrigation flow

Tank mix order (for safety)

1. Fill tank 50-75% with water; start agitation.
2. Wettable powders / dispersible granules first. Pre-mix in a bucket of water before adding to tank to avoid clumping.
3. Suspension concentrates / flowables. Pour slowly with agitation.
4. Soluble liquids. Including most herbicides.
5. Emulsifiable concentrates (oils). Last to avoid foaming.
6. Adjuvants (surfactants, crop oils). Add after pesticide; right before topping off.
7. Top off with water. Maintain agitation throughout.
8. Use immediately. Don't store mixed tanks overnight; pesticides degrade in solution.

PPE requirements (typical)

Toxicity / Signal Word	Minimum PPE
DANGER (highest)	Full chemical suit, respirator, goggles, chemical gloves, boots, hat — when handling concentrate. Restricted Use Pesticide license often required.
WARNING	Long sleeves, pants, chemical gloves, goggles, respirator (mixing only), waterproof boots
CAUTION	Long sleeves, pants, chemical gloves, eyewear, waterproof boots
Organic / OMRI listed	Same as conventional in same toxicity tier — OMRI ≠ safe

Always read the actual label. PPE varies by product and life stage of the spraying activity (mixing, applying, post-application).

Calibration check

Before any spray, calibrate. Method:

1. Measure area you'll spray a known time (e.g., 1 minute at typical pace).
2. Catch all output during that minute (use buckets at each nozzle).
3. Calculate gallons per acre: gallons captured / area sprayed × area in acres factor.
4. Verify matches your label-required water rate. Adjust nozzles or speed to match.

Free under CC BY 4.0. Cite as "OAT Pesticide Spray Calculator (openagriculturetechnology.com)". Always read and follow product label — label is the law. PPE per EPA WPS standards.