Volume · Unit Converter

Convert Imperial Fluid Ounce to Milliliter

Convert imperial fluid ounces to milliliters instantly. 1 imperial fluid ounce = 28.4130625 milliliter — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Milliliter to Imperial Fluid Ounce converter for the reverse conversion.

Written by Sunith Babu L, Ph.D., Lead Engineer Reviewed by Dr. Jaya Christiyan K G, Ph.D.
Volume category 2 min read Published Last reviewed Updated

Units explained

Imperial (UK)

Imperial Fluid Ounce

What is a imperial fluid ounce?

An imperial fluid ounce is 1/160 of an imperial gallon (28.4131 mL).

Origin of the imperial fluid ounce

Defined so that ten fluid ounces make an imperial half-pint.

Where it is used

Used in UK and Commonwealth recipes and labels.

When and where it was developed

UK, 1824.

Metric / SI

Milliliter

What is a milliliter?

A milliliter is one thousandth of a liter, exactly equal to one cubic centimeter.

Origin of the milliliter

Formed with the SI prefix milli- applied to the liter.

Where it is used

The standard small-volume unit in cooking, medicine and the laboratory.

When and where it was developed

Metric prefix system.

Imperial Fluid Ounce to Milliliter conversion formula

The relationship between imperial fluid ounces and milliliters:

1 fl oz = 28.4130625 mL
1 mL = 0.0351950797 fl oz

To convert imperial fluid ounces to milliliters, multiply the value in imperial fluid ounces by 28.4130625. To reverse, multiply milliliters by 0.0351950797.

How to use this converter

Type a value into the calculator. The result in milliliters updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Milliliter to Imperial Fluid Ounce converter for the reverse direction.

Step-by-step: convert imperial fluid ounces to milliliters

  1. Write down the value in imperial fluid ounces (fl oz).
  2. Multiply that value by the factor 28.4130625.
  3. The product is the equivalent value in milliliters (mL).
  4. To reverse, multiply the milliliter value by 0.0351950797.

Worked examples

Example 1 — Convert 1 fl oz to mL:
1 × 28.4130625 = 28.4130625 mL

Example 2 — Convert 100 fl oz to mL:
100 × 28.4130625 = 2841.30625 mL

Real-world example — Plastic-film thickness alternates

A 150-imperial fluid ounce plastic film converts cleanly to milliliters — useful for packaging buyers reconciling supplier datasheets across metric and US measurement systems.

150 fl oz × 28.4130625 = 4261.959375 mL

Real-world example — Hair-width scale measurements

A 70-imperial fluid ounce measurement (about the diameter of a human hair) is the kind of value materials engineers regularly express in adjacent micro-scale units like milliliters for direct comparison across supplier datasheets.

70 fl oz × 28.4130625 = 1988.914375 mL

Real-world example — Paper and film thicknesses

At the thickness of office paper (roughly 3 imperial fluid ounces), converting between sub-millimeter units is routine for packaging and printing buyers comparing quotes from metric and US suppliers.

3 fl oz × 28.4130625 = 85.2391875 mL

Imperial Fluid Ounce to Milliliter conversion table

Standard reference values for converting imperial fluid ounces to milliliters:

Imperial Fluid Ounce [fl oz]Milliliter [mL]
0.010.284130625
0.12.84130625
128.4130625
256.826125
385.2391875
4113.65225
5142.0653125
10284.130625
20568.26125
30852.391875
401136.5225
501420.653125
1002841.30625
50014206.53125
100028413.0625

Frequently asked questions

How many milliliters is 1 imperial fluid ounce?
1 imperial fluid ounce equals 28.4130625 milliliter.
How do I convert imperial fluid ounces to milliliters?
Multiply the value in imperial fluid ounces by 28.4130625 to get milliliters.
How do I convert milliliters back to imperial fluid ounces?
Multiply the value in milliliters by 0.0351950797, or use the Milliliter to Imperial Fluid Ounce converter.
How many milliliters is 100 imperial fluid ounces?
100 imperial fluid ounces equals 2841.30625 milliliters, because 100 × 28.4130625 = 2841.30625.

Convert Imperial Fluid Ounce to other volume units

Show all Imperial Fluid Ounce conversions

Sources & references

Conversion factor (1 fl oz = 28.4130625 mL) verified against the following authoritative sources:

Results are provided for general reference. Verify critical measurements against an authoritative standard.