Herbicide mixing calculators
Dial in oz-per-gallon weed control batches for spot sprayers, backpacks, and skid tanks without a conversion chart.
These presets cover the oz-per-gallon rates lawn crews and land managers pull from herbicide labels—from light 1 oz turf edging mixes to 10 oz bare-ground sterilants before gravel work.
Each calculator preloads the MixByParts modal with your target container so you can scale label rates, flip to weight mode with density defaults, and copy the ready-made label line for compliance logs.
Use them to plan a spray day: adjust total volume for multi-acre coverage, export grams for scale mixing, or duplicate a preset to test surfactant tweaks before you load the tank.
Popular use cases
- Prepping a 2 oz per gallon glyphosate batch in a 4 gallon backpack sprayer
- Filling 32 oz trigger bottles for driveway cracks at 4 oz per gallon
- Scaling 6 oz per gallon bare-ground mix to a 15 L skid sprayer
Common mistakes
- Skipping label rate ceilings
More ounces per gallon is not always better—going past the labelled maximum can stunt turf or violate local regulations. Confirm the product’s per-acre and per-application limits before scaling batches.
- Ignoring water quality
Hard water, high pH, or dirty tanks can deactivate active ingredients. When labels recommend it, add ammonium sulfate or buffering agents before the herbicide and keep tanks rinsed between jobs.
- Not triple-rinsing sprayers
Residue from total vegetation mixes can injure ornamentals the next time you spray. Run a triple rinse with detergent and ammonia (per label) after every use, then flush hoses and tips.
Plan a backpack herbicide batch
Launch the mixer with a 2 oz per gallon preset sized for a 4 gallon backpack (≈15 L). Adjust total volume, swap units, or tweak density before you fill the tank.
Defaults: 4 gal total, 2 oz concentrate per gallon (≈1:63).
Herbicide presets by sprayer type
Spot spraying bottles
Ready-to-use jugs and trigger bottles for turf edges and cracks.
Backpack sprayers (15–20 L)
Quick conversions for 4 gallon backpacks and 15 L pump sprayers.
Pasture & fence line control
Higher-rate mixes sized for 1 gallon jugs and refills.
Metric conversions & small batches
Convert oz-per-gallon labels into milliliter containers for lab testing.
Guides & resources
Featured calculators
FAQs
Can I change the water volume without altering the oz-per-gallon rate?
Yes. Inside the mixer, edit the Total volume field to the batch size you need—the concentrate and carrier amounts update instantly while keeping the same oz-per-gallon ratio.
How do I convert these oz-per-gallon rates to milliliters per liter?
Switch the unit selector to liters or milliliters. The calculator automatically translates each preset (1 gallon = 3.785 L) so you can stage metric containers or lab tests without redoing the math.
What density should I use when weighing herbicides?
Most systemic herbicides sit near 1.08–1.12 g/mL. The presets default to 1.10 g/mL for the concentrate, but you can overwrite the density field with the value from your SDS for more accurate gram outputs.