Femtoliter is 1e-15 liter units.
Femtoliters to Fluid ounces Converter — fL to fl oz
Convert Femtoliter (fL) to Fluid ounce (fl oz) using the exact conversion factor (1 femtoliter = 3.381402e-14 fluid ounce). See the formula, worked examples, conversion table, history, and common uses.
Femtoliters to Fluid ounces converter
Converter
Volume Converter
Convert metric, US customary, imperial, cooking, dry, and industrial volume units.
Context values
Some unit families need one extra value for a physically accurate result.
A US fluid ounce is 1/128 of a US gallon.
Result = input x 1e-18 / 2.95735296e-5.
Volume uses the cubic meter as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Femtoliters to Fluid ounces
Femtoliter and Fluid ounce appear side by side at fuel pumps and on beverage labels, since the US measures liquids in gallons while most of the world uses liters. Specifically: Femtoliter is 1e-15 liter units, and a US fluid ounce is 1/128 of a US gallon.
Formula
fluid ounces = femtoliters × 3.381402e-14
This factor comes from each unit's defined relationship to the category's base unit: 1 femtoliter equals 1e-18 base units, and 1 fluid ounce equals 0.0000295735295625 base units, so dividing one by the other gives the direct femtoliter-to-fluid ounce factor of 3.381402e-14.
Simple example
1 fL × 3.381402e-14 = 3.381402e-14 fl oz
1 femtoliter = 3.381402e-14 fluid ounces.
Real-world example
10 fL × 3.381402e-14 = 3.381402e-13 fl oz
10 femtoliters = 3.381402e-13 fluid ounces.
Conversion table
| Femtoliter (fL) | Fluid ounce (fl oz) |
|---|---|
| 1 fL | 3.381402e-14 fl oz |
| 5 fL | 1.690701e-13 fl oz |
| 10 fL | 3.381402e-13 fl oz |
| 25 fL | 8.453506e-13 fl oz |
| 50 fL | 1.690701e-12 fl oz |
| 100 fL | 3.381402e-12 fl oz |
Reverse conversion: Fluid ounce to Femtoliter
3.381402e-14 fl oz × 2.957353e+13 = 0.9999999201 fL
3.381402e-14 fluid ounces = 0.9999999201 femtoliters.
femtoliters = fluid ounces × 2.957353e+13
For a page dedicated to this direction, see Fluid ounce to Femtoliter.
Understanding the Femtoliter (fL)
Femtoliter is 1e-15 liter units.
Understanding the Fluid ounce
Fluid ounce (fl oz) measures volume. The US fluid ounce is 1/128 of a US gallon: exactly 29.5735295625 milliliters. It is classified as a US customary unit.
Where it's used: United States (beverage, nutrition labeling)
Uses of the Fluid ounce today
- US beverage container sizing (soda, water bottles)
- US nutrition and medication dosing labels
History of the Fluid ounce
The US fluid ounce follows from the same English wine-gallon system as the rest of the US liquid volume units, defined as a consistent fraction of the gallon.
Historical origin. Fluid ounce was not the invention of a single named person; it developed through the process described above.
Fluid ounce — sources
- NIST Handbook 44, Appendix C — General tables of units including the US fluid ounce definition.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many fluid ounces are in 1 femtoliter?
1 femtoliter equals 3.381402e-14 fluid ounces, using the exact defined conversion factor rather than an estimate.
How do I convert femtoliter to fluid ounce?
Multiply the femtoliter value by 3.381402e-14. The converter above does this instantly to whatever precision you set.
How do I convert fluid ounce back to femtoliter?
Use the reverse factor: 1 fluid ounce equals 2.957353e+13 femtoliters. You can also use the swap control in the converter above to flip the direction instantly.
What is a femtoliter?
Femtoliter (fL) is a unit of volume.
What is a fluid ounce?
Fluid ounce (fl oz) measures volume. The US fluid ounce is 1/128 of a US gallon: exactly 29.5735295625 milliliters. It is classified as a US customary unit.
Is the femtoliter to fluid ounce conversion exact?
Yes. The US fluid ounce is 1/128 of a US gallon: exactly 29.5735295625 milliliters. That fixed definition is what the converter above uses, so any rounding you see is a display choice, not a limitation of the math.