Ounces to Cups Converter
Convert fluid ounces (oz) to cups instantly. Essential for cooking, baking, meal prep, nutrition, beverages, and food production.
What the ounces to cups converter does
The ounces to cups converter turns a volume in US fluid ounces into cups. Enter the number of fluid ounces, choose which cup you mean, US, metric or imperial, and press Calculate. The three cups differ in size, so the choice matters for anything beyond a rough estimate.
The three cup sizes
| Cup | Volume | US fluid ounces per cup | Formula used |
|---|---|---|---|
| US customary cup | 236.6 mL | 8 | cups = oz ÷ 8 |
| Metric cup (Australia, NZ, Canada recipes) | 250 mL | 8.45 | cups = oz × 29.5735 ÷ 250 |
| Imperial cup (older UK recipes) | 284.1 mL | 9.61 | cups = oz × 29.5735 ÷ 284.131 |
The converter treats the input as US fluid ounces (29.5735 mL). An imperial fluid ounce is slightly smaller at 28.41 mL; if you are reading an old British recipe in fluid ounces, multiply by 0.961 first.
Worked examples
| Fluid ounces | US cups | Metric cups | Imperial cups |
|---|---|---|---|
| 4 | 0.5 | 0.473 | 0.416 |
| 8 | 1 | 0.946 | 0.833 |
| 12 | 1.5 | 1.420 | 1.249 |
| 16 | 2 | 1.892 | 1.665 |
| 32 | 4 | 3.785 | 3.331 |
Fluid ounces versus ounces by weight
This is the source of most conversion errors in the kitchen. A fluid ounce is a volume; an ounce (avoirdupois) is a weight of 28.35 g. They coincide only for water and similar liquids: 8 fl oz of water weighs about 8.3 oz. For other ingredients the difference is large. One US cup of all-purpose flour weighs about 4.25 oz (120 g), so “8 ounces of flour” is nearly two cups, not one. A cup of honey weighs 12 oz. If a recipe gives ounces for a dry ingredient, it almost always means weight, and a kitchen scale is the right tool. The grams to ounces calculator and the ingredient weight to volume converter cover that case.
Common kitchen quantities
- 1 US cup = 8 fl oz = 16 tablespoons = 48 teaspoons = 236.6 mL
- 1 US pint = 2 cups = 16 fl oz
- 1 US quart = 4 cups = 32 fl oz
- 1 US gallon = 16 cups = 128 fl oz
- 1 litre = 33.8 fl oz = 4.23 US cups
- A standard can of soda = 12 fl oz = 1.5 cups
Measuring accurately
Liquid measuring cups have a spout and markings below the rim; read them at eye level on a flat surface. Dry measuring cups are filled level with the rim. Using a dry cup for liquid or vice versa introduces errors of 5 to 10%, which is harmless in soup but noticeable in baking. For volumes under 2 fl oz, tablespoons (0.5 fl oz each) are easier to measure precisely.
Common mistakes
- Using the US cup for an Australian recipe. The 5.5% difference adds up in large batches.
- Weighing fluid ounces. Only water-like liquids weigh the same number of ounces as their volume.
- Confusing the Japanese cup. Rice cooker cups are 180 mL, about 6.1 fl oz.
- Rounding too early. Convert the whole recipe, then round each ingredient once.
Related tools
The volume converter handles millilitres, litres, pints and gallons. The drops to mL converter covers very small volumes, the gallons to pounds converter and kg to gallons converter switch between volume and weight for liquids, and the density converter supplies the factor for other substances.
External references
Frequently asked questions
How many cups is 8 oz?
8 US fluid ounces is exactly 1 US cup. For a metric cup it is 0.95 cups.
Is a coffee cup one cup?
Usually not. A typical mug holds 10 to 12 fl oz, and coffee makers often count a “cup” as 5 or 6 fl oz.
How many ounces are in half a cup?
4 US fluid ounces, or 8 tablespoons.
Which cup do UK recipes use?
Modern UK recipes mostly give grams and millilitres. Where cups appear they are usually the 250 mL metric cup; very old ones may mean the 284 mL imperial cup.
Can I convert dry ounces with this tool?
No. Dry ounces are weight. Use the ingredient weight to volume converter, which knows the density of common ingredients.