How It Works
This calculator works in 4 steps.
Enter the label rate
Type the ratio or the oz per gallon for the claim being used.
Enter the contact time
Type the wet contact time from the same label claim.
Enter the container size
Type the volume of the bottle, bucket, or dispenser.
Read the amounts
The calculator returns concentrate and water amounts with the contact time reminder.
The Formula
The formula scales the label rate to the container volume.
V_conc = (oz/gal) × gallonsoz/gal = 128 / XmL per L = 1,000 / X- X:
- Ratio term on the label
- oz/gal:
- US fluid ounces per US gallon
A quaternary ammonium disinfectant labeled 1:64 (2 fl oz per gallon) needs 6 fl oz (177 mL) for a 3-gallon bucket.
Conversion Table
The conversion table converts 5 common label ratios into amounts per US gallon and per liter.
| Label ratio | Per US gallon (fl oz) | Per US gallon (mL) | Per 1 L (mL) |
|---|---|---|---|
| 1:32 | 4 fl oz | 118.3 mL | 31.25 mL |
| 1:64 | 2 fl oz | 59.15 mL | 15.62 mL |
| 1:128 | 1 fl oz | 29.57 mL | 7.812 mL |
| 1:256 | 0.5 fl oz | 14.79 mL | 3.906 mL |
| 1:512 | 0.25 fl oz | 7.393 mL | 1.953 mL |
128 US fl oz = 1 US gallon. Use the rate printed on the product label.
What Is the Disinfectant Dilution Calculator?
The Disinfectant Dilution Calculator is a tool that applies the directions on a registered disinfectant's label, such as 2 fl oz per gallon (1:64), to the user's container size. The calculator scales the label rate; it does not create new rates.
In the United States, the Environmental Protection Agency (EPA) registers disinfectants, and the label lists the dilution, contact time, and surfaces for each claim. A rate below the label rate may not meet the claim, and a rate above it may damage surfaces or exceed residue limits. The calculator asks for the label rate and the claim's contact time and prints both on the result.
Common Uses
There are 5 main uses of this calculator.
Healthcare surfaces
Environmental services teams mix label-rate disinfectants.
Schools
Custodians scale label rates to classroom buckets.
Food service
Kitchens apply food-contact sanitizer rates.
Veterinary clinics
Staff mix kennel disinfectants per the label.
Gyms and fitness centers
Staff fill spray bottles at label rate.