If you’re applying herbicide to your lawn, garden, or property, you know how important it is to mix your solution correctly. Whether you’re using a backpack sprayer, hand pump sprayer, or an ATV sprayer, the last thing you want to do is waste product—or worse, apply the wrong rate and damage your plants or turf.
This free Herbicide Mixing Calculator takes the guesswork out of your sprayer calculations. It’s designed to help you figure out exactly how much herbicide product to mix based on the size of your treatment area and the rate listed on the herbicide label (in ounces per 1,000 square feet).
With our calculator, you can now also enter your tank size in gallons and receive custom mixing instructions—including your water-to-product ratio. It’s the perfect tool for DIY homeowners, acreage managers, and anyone who needs fast, reliable herbicide rate calculations.
Use the Herbicide Rate Calculator Below
Herbicide Mixing Calculator
Who Is This Calculator For?
This tool is ideal for:
- Homeowners treating lawns for weeds and pests
- DIY lawn care pros using tank, backpack, or hose-end sprayers
- Landowners and rural property managers spraying pastures or food plots
- Anyone looking to mix liquid herbicides with precision and confidence
When to Use It
Use this calculator anytime you need to:
- Mix a tank of herbicide for a specific lawn or area
- Determine the amount of herbicide to apply per 1,000 sq ft or per acre
- Calculate how much product to add to a 1, 2, or 4-gallon sprayer
- Get the correct water-to-herbicide mix ratio for your equipment
Herbicide Mixing FAQs & Sprayer Tips
How do I know the right herbicide rate to use?
Always read the label on your herbicide product. Most liquid herbicides list application rates in ounces per 1,000 square feet or per acre. Use those numbers in this calculator to get an accurate mix amount based on the size of your lawn or treatment area.
For more information, see my full guides to spray volume per acre and formulas to calibrate your sprayer.
How much water should I mix with the herbicide?
The amount of water you use depends on your sprayer type and your desired spray coverage, not the herbicide rate. Most herbicides don’t require a specific water volume—they just need to be applied at the correct product rate across the area. For example, if your sprayer applies 1 gallon of mix per 1,000 sq ft, you’d simply dissolve the correct amount of product into that gallon.
Tip: Always do a test spray to see how much area your sprayer actually covers with 1 tank.
Can I use this calculator with selective or non-selective herbicides?
Yes. This herbicide rate calculator works for both selective herbicides (like 2,4-D or weed-and-feed products) and non-selective herbicides (like glyphosate or total vegetation killers). Just make sure you’re using the correct rate based on the label instructions.
Tips for Using Different Sprayer Types
Handheld & Pump Sprayers (1–2 gallons)
- Ideal for spot-treating weeds in gardens, driveways, and small lawns.
- Calibrate your sprayer by spraying a known area and measuring how much liquid it uses.
- Mix only as much as you plan to use that day.
Backpack Sprayers (4 gallons)
- Great for medium-sized lawns or larger spot treatments.
- Label each sprayer with dedicated use (herbicide only, insecticide only, etc.) to avoid contamination.
- Rinse thoroughly between uses to extend sprayer life.
ATV & Pull-Behind Sprayers (15–25+ gallons)
- Best for large lawns, acreage, or pasture work.
- Use a pressure regulator on the sprayer for even coverage.
- Calibrate the sprayer before you mix your pesticide/herbicide