Use the unit system written on the label. US and Imperial gallons and fluid ounces have different sizes; the manufacturing country alone does not identify the unit. 1L = 1000 mL.
Volume conversion reference
| Volume unit | Milliliters |
|---|---|
| 1 US fl oz | ≈ 29.57353 mL |
| 1 US gal | ≈ 3785.412 mL |
| 1 Imperial fl oz | ≈ 28.41306 mL |
| 1 Imperial gal | 4546.09 mL |
These displayed conversions follow NIST's conversion table; ≈ marks rounded values. oz is a mass unit, whereas fl oz is a volume unit. A powder amount in grams needs its specified mass measurement; it cannot be replaced with the same number of mL.
Example: a dose per gallon of water
Suppose an instruction specifies 5 mL concentrate per US gallon of water. For 500 mL water, the dose is:
500 ÷ 3785.412 × 5 ≈ 0.66 mL, rounded to two decimals.
Here 500 mL is the water amount, not the finished total. This is a hypothetical dose used to show the conversion, not a recommendation for a product.
Example: a US fl oz package and a 1:10 ratio
16 US fl oz ≈ 473.18 mL describes the package size. It does not determine the mixing ratio. If an instruction separately specifies concentrate:water 1:10, making 1000 mL total needs approximately 90.91 mL concentrate and 909.09 mL water.
Starting with 1000 mL water instead requires 100 mL concentrate, giving 1100 mL total. A concentrate-to-total 1:10 instruction is a different definition; see ratio basis.
Select units in the app
The Dilution Ratio Calculator instructions supports mL, L, US fl oz and US gal. Its fl oz and gal conversion factors are US values. For an Imperial instruction, convert the amount to mL or L first. Enter the known concentrate, water or total in the appropriate mode and check the result unit before measuring.