Embrace the metric system by learning how to convert milliliters to liquid ounces. Both milliliters and ounces -- an Imperial system unit -- measure the volume of a substance, but you will not likely encounter the metric measure regularly in the United States. You can use a conversion factor to prepare European recipes when using American measuring cups with markings in fluid ounces. Once you know how to convert milliliters to ounces, you can also convert from ounces to milliliters and from liters to ounces.

Multiply the number of milliliters by 0.0338 to find the number of ounces. For example, suppose you have want to convert 100 milliliters of water to ounces. You would multiply 100 by 0.0338 to get 3.38 ounces.

Convert a number of ounces to milliliters by multiplying the number of ounces by 29.573. For example, convert 10 ounces to milliliters by multiplying 10 by 29.573. The product is 295.73 milliliters.

Check your conversion from milliliters to ounces by multiplying your answer by 29.573 milliliters to see if you get your original number of milliliters. For instance, to check your answer of 3.38 ounces in Step 1, multiply 3.38 by 29.573 to get 99.956. This rounds up to 100 milliliters, so you know your math is correct.