A fluid ounce (US) is a unit of volume used to measure liquids in the U.S. customary system. It's abbreviated as fl oz and is commonly seen in cooking, nutrition labeling, and liquid packaging. One US fluid ounce is defined as 1/128 of a US gallon, which equals exactly 29.5735 milliliters.
Despite the term "ounce" also being used for weight, a fluid ounce specifically measures liquid volume. It's important to distinguish the two, especially in recipes or products where both liquid and solid measurements appear. The US fluid ounce is a standard unit across many industries, from beverages and sauces to cleaning products and personal care items,
Uses: The fluid ounce is widely used in everyday life throughout the United States. In the kitchen, it shows up in recipes for measuring water, milk, oil, and other liquids. You'll also find it on nutrition labels, drink containers, and liquid medicine bottles. Most bottled drinks sold in the U.S., from soda cans to sports drinks, are labeled in fluid ounces.
Outside the kitchen, fluid ounces are also used to measure everyday products like shampoo, lotion, and household cleaners. Packaging labels often list fluid ounces to help shoppers gauge how much liquid is inside each bottle. In pharmacies, you may still see fluid ounces on medication packaging, though many prescriptions now use milliliters for greater accuracy and consistency.
The imperial fluid ounce is a unit of volume from the imperial measurement system, traditionally used in the United Kingdom and other Commonwealth countries. One imperial fluid ounce is equal to 28.4131 milliliters, which makes it slightly larger than the US fluid ounce (approximately 29.57 mL in the US system). It's commonly abbreviated as fl oz and was widely used for measuring liquids in recipes, packaging, and day-to-day household tasks.
Uses: The imperial fluid ounce was once a standard unit in British kitchens, used to measure ingredients such as milk, oil, and other cooking liquids. While most modern recipes in the UK now use milliliters or grams, many older or traditional recipes still list quantities in fluid ounces. This makes the unit especially relevant for those cooking from classic British cookbooks or following long-standing family recipes.
The imperial fluid ounce still appears on many UK labels, especially for drinks, personal care products, and older medicinal packaging. Whether you're following a traditional recipe or measuring from labeled packaging, knowing how this unit works helps you convert accurately and maintain consistency.
1 fl oz = 1.04084 fl oz (imp)
Let’s say you want to convert 100 fl oz to fl oz (imp).
Using the formula:
100 × 1.04084 = 104.084 fl oz (imp)
So, 100 fl oz is approximately 104.084 fl oz (imp).
| Fluid Ounce (US) (fl oz) | Fluid Ounce (Imperial) (fl oz (imp)) |
|---|---|
| 1 fl oz | 1.041 fl oz (imp) |
| 2 fl oz | 2.082 fl oz (imp) |
| 3 fl oz | 3.123 fl oz (imp) |
| 4 fl oz | 4.163 fl oz (imp) |
| 5 fl oz | 5.204 fl oz (imp) |
| 6 fl oz | 6.245 fl oz (imp) |
| 7 fl oz | 7.286 fl oz (imp) |
| 8 fl oz | 8.327 fl oz (imp) |
| 9 fl oz | 9.368 fl oz (imp) |
| 10 fl oz | 10.408 fl oz (imp) |
| 11 fl oz | 11.449 fl oz (imp) |
| 12 fl oz | 12.49 fl oz (imp) |
| 13 fl oz | 13.531 fl oz (imp) |
| 14 fl oz | 14.572 fl oz (imp) |
| 15 fl oz | 15.613 fl oz (imp) |