Milliliters (ml) and ounces (oz) are units of volume, but they are from different measurement systems (metric and imperial). There are two main types of ounces: fluid ounces (fl oz) and avoirdupois ounces.

Here's how to convert milliliters to ounces:

* Milliliters to Fluid Ounces (US): 1 ml = 0.033814 fl oz (US)

* Milliliters to Fluid Ounces (UK): 1 ml = 0.035195 fl oz (UK)

* Milliliters to Avoirdupois Ounces: This conversion is not applicable because avoirdupois ounces are a unit of weight, not volume.

Example:

To convert 250 ml to fluid ounces (US):

250 ml x 0.033814 fl oz/ml = 8.4535 fl oz (US)

Remember: When converting between milliliters and ounces, it's important to specify which type of ounce you are using (US or UK).