Every product label gives a rate in ounces per gallon. Multiply that rate by your tank size and you know exactly how much concentrate to pour — no guesswork, no waste.
A 4-gallon tank at 1.5 oz per gallon needs 6 oz of concentrate — measure once and fill.
The example
Three jobs, each with a tank size and the product's label rate.
| A | B | C | D | |
|---|---|---|---|---|
| 1 | Product | Tank (gal) | Oz / gal | Concentrate (oz) |
| 2 | General spray | 4 | 1.5 | 6.0 |
| 3 | Perimeter | 2 | 2 | 4.0 |
| 4 | Termite pre-treat | 25 | 0.8 | 20.0 |
The formula
One multiplication does it:
How it works
The label rate is per gallon, so scaling to a full tank is a simple product:
B2is the volume of water in your tank, in gallons.C2is the mix rate printed on the product label, in ounces per gallon.- Multiplying the two gives the total concentrate to add for that tank.
Always add concentrate to a partly filled tank, then top off with water, to mix evenly.
Try it: interactive demo
Enter your tank size and the label's ounces-per-gallon rate.
Variations
Mix to a percent solution
For a percent-based label, multiply tank ounces by the percent instead.
Pitfalls & errors
Read the label units carefully — some give oz per gallon, others oz per 100 gallons. Mixing them up over- or under-doses the tank.
Keep a tank-size column so you can dial the same rate into a 1-gallon hand sprayer or a 25-gallon rig with the same formula.
Practice workbook
Frequently asked questions
My label says oz per 100 gallons. Now what?
Can I solve for tank size instead?
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