40 milliliters to US fluid ounces
1.35 fl oz
40 mL = 1.35 fl oz.
US fluid ounces
1.35fl oz
40 mL = 1.35 fl oz
In short
How many US fluid ounces is 40 milliliters?
40 mL = 1.35 fl oz. 1 milliliter = 0.033814 US fluid ounces, so the working is 40 × 0.033814 = 1.35.
The working
The factor below is an exact definition rather than a measurement, so nothing is approximated in the arithmetic. The only rounding on this page happens where a number is displayed.
1 milliliter = 0.033814 US fluid ounces 40 × 0.033814 = 1.35
How much precision do you need?
Each row is the same answer cut at a different number of decimals, with what that choice costs you. Pick the shortest row whose error is smaller than whatever you are measuring with.
| Rounded to | Answer (fl oz) | Off by |
|---|---|---|
| Whole number | 1 | −0.35256 |
| 1 decimal | 1.4 | +0.04744 |
| 2 decimals | 1.35 | −0.00256 |
Round trip: take 1.35 fl oz back the other way and you land on 39.9243 mL — a drift of 0.0757 mL. That gap is the rounding, not the conversion.
Frequently asked questions
What is 40 milliliters in US fluid ounces?
40 milliliters is 1.35 US fluid ounces. 1 milliliter = 0.033814 US fluid ounces, so the working is 40 × 0.033814 = 1.35.
How accurate is 1.35 fl oz?
Rounding to 1.35 fl oz and converting straight back gives 39.9243 mL, a drift of 0.0757 mL from the 40 you started with. The factor itself is exact; every bit of that difference comes from the rounding, not the conversion.
Nearby values
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