Milliliters to fluid ounces (mL to fl oz) converter

What is a milliliters to fluid ounces converter?

A milliliters to fluid ounces converter is an online tool that translates a volume given in milliliters into its equivalent in fluid ounces, and back again. It connects the metric system, where the milliliter is the everyday small-volume unit, with the imperial and US customary systems, where the fluid ounce is still widely used for drinks, recipes, and bottle labelling. Because product packaging, cookbooks, and medical dosing instructions often mix these systems depending on the country, a quick and reliable conversion saves time and prevents mistakes.

US and UK fluid ounces

The fluid ounce is not a single fixed quantity. There are two common versions: the US fluid ounce (US fl oz) and the UK, or imperial, fluid ounce (UK fl oz). One US fluid ounce equals 29.5735 milliliters, while one UK fluid ounce equals 28.4131 milliliters. The UK ounce is the smaller of the two, so for the same number of ounces the imperial measure represents slightly less liquid. Always check which standard a recipe or label uses before converting, especially when working across borders.

How does the converter work?

You enter a value in one field, choose the unit for each side, and the matching value appears instantly in the other field. The milliliters side accepts milliliters (mL) or liters (L), and the fluid ounces side accepts US fluid ounces (fl oz US) or UK fluid ounces (fl oz UK). Internally the tool converts your input to a common base volume and then expresses it in the target unit, so the conversion stays accurate regardless of which direction you work in.

Formula for conversion

To convert between milliliters and fluid ounces, use the following relationships.

For milliliters to US fluid ounces: $\text{fl oz (US)} = \frac{\text{mL}}{29.5735}$

For US fluid ounces to milliliters: $\text{mL} = \text{fl oz (US)} \times 29.5735$

For milliliters to UK fluid ounces: $\text{fl oz (UK)} = \frac{\text{mL}}{28.4131}$

For UK fluid ounces to milliliters: $\text{mL} = \text{fl oz (UK)} \times 28.4131$

Conversion table

The table below shows common milliliter volumes alongside their equivalents in US and UK fluid ounces.

Examples

Example 1: 100 mL to US fluid ounces

To convert 100 milliliters to US fluid ounces, divide by 29.5735:

$\frac{100}{29.5735} = 3.3814 \text{ fl oz (US)}$

Example 2: 1 US fluid ounce to milliliters

To convert 1 US fluid ounce to milliliters, multiply by 29.5735:

$1 \times 29.5735 = 29.5735 \text{ mL}$

Example 3: 500 mL to US fluid ounces

A 500 mL bottle of water converts to US fluid ounces as follows:

$\frac{500}{29.5735} = 16.907 \text{ fl oz (US)}$

Example 4: 100 mL to UK fluid ounces

Using the imperial standard of 28.4131 mL per fluid ounce:

$\frac{100}{28.4131} = 3.5195 \text{ fl oz (UK)}$

Notes

• Remember that US and UK fluid ounces are not the same size: 29.5735 mL versus 28.4131 mL.
• The converter handles decimals, so partial volumes such as 12.5 mL convert just as accurately as whole numbers.
• When following a recipe, match the ounce standard to the recipe’s country to avoid measuring errors.
• Switching the unit selectors changes how the number you already typed is interpreted, so set the units before entering your value.

Frequently asked questions

How many milliliters are in 1 US fluid ounce?

One US fluid ounce equals 29.5735 milliliters. To go the other way, divide a milliliter value by 29.5735 to get US fluid ounces.

How many fluid ounces are in 100 mL?

100 milliliters equal about 3.3814 US fluid ounces, or about 3.5195 UK fluid ounces. The exact figure depends on which fluid ounce standard you use.

What is the difference between US and UK fluid ounces?

A US fluid ounce is 29.5735 mL, while a UK (imperial) fluid ounce is 28.4131 mL. The UK ounce is slightly smaller, so the same ounce count holds a little less liquid.

How do I convert milliliters to fluid ounces?

Divide the number of milliliters by 29.5735 for US fluid ounces, or by 28.4131 for UK fluid ounces. For example, 250 mL is about 8.45 US fluid ounces.

Can this converter handle liters as well?

Yes. The milliliters side lets you select liters (L) instead of milliliters (mL), so you can convert larger volumes directly into fluid ounces. If you need fluid ounces back to milliliters, use our fluid ounce to milliliter converter.

Why might my result look slightly off?

Make sure you have selected the correct fluid ounce standard (US or UK) and that the units were chosen before typing the value. Rounding to fewer decimal places can also make small differences appear.