Ounces to Cups Calculator
Fluid ounces to cups is simple: 8 US fluid ounces make 1 US cup. Ounces by weight are different, because the number of cups depends on the ingredient, so you choose one first.
Last updated November 4, 2026
0 to 1,000,000.
Result
8 US fl oz = 1 cup
| Measure | Amount |
|---|---|
| US cups | 1 |
| US fluid ounces (same volume) | 8 |
| Tablespoons | 16 |
Fluid ounces measure volume, so this needs no ingredient. US cups only: 1 cup = 8 US fl oz = 236.588 mL.
Show the work
Formula: cups = fluid ounces ÷ 8
- 1 US cup = 8 US fluid ounces; no ingredient is involved because both are volumes.
- Cups: 8 fl oz ÷ 8 = 1 cups.
Result: 8 US fl oz = 1 cup
How ounces convert to cups
fluid ounces: cups = fl oz ÷ 8
weight: cups = (ounces × 28.3495 g) ÷ grams per cup of the ingredient
There are two kinds of ounce in a kitchen. A fluid ounce measures volume. In the US customary system a cup is exactly 8 fluid ounces, or 236.5882 mL, so cups equal fluid ounces divided by 8. No ingredient is involved.
An ounce of weight is one sixteenth of a pound, 28.3495 grams. To turn weight into cups the calculator first converts ounces to grams, then divides by the approximate grams per cup of the ingredient you picked. The figures come from the King Arthur Baking ingredient weight chart, for example 120 g per cup of all-purpose flour and 227 g for water.
This page is US customary only. It does not convert to metric or imperial cups.
See how we calculate for the formulas, sources and review schedule behind every calculator.
Also useful alongside this calculator: Pounds to Kilograms Calculator.
Fluid ounces versus ounces by weight
The word ounce is used for both volume and weight, which causes most mistakes. A measuring cup marked in ounces shows fluid ounces. A kitchen scale showing ounces shows weight. The two agree closely only for water and similar liquids: 8 fluid ounces of water weigh about 8 ounces (227 g per cup in the chart).
For flour the gap is large. One cup is 8 fluid ounces, but it weighs only about 4.2 ounces, since 120 g divided by 28.3495 g is 4.23 oz. Reading a 4-ounce bag weight as 4 fluid ounces, or the reverse, gives a wrong amount of flour.
Why ounces by weight need an ingredient
Eight ounces of honey and eight ounces of flour weigh the same but fill very different cups. Honey is dense and packs 336 g into a cup, while flour packs 120 g. A single ounces-to-cups number would be wrong for one of them.
When you choose a weight option without an ingredient, the calculator shows a message asking you to pick one. It never quietly treats weight as volume.
How approximate the weight results are
Ingredient weights vary with how you fill the cup. Flour that is scooped weighs more than flour that is spooned and levelled, sifting lightens it, and brown sugar is packed. Brands also differ slightly. Treat weight-based cup answers as close estimates and use a scale when a recipe depends on accuracy.
Limits and rounding
The amount must be from 0 to 1,000,000. Answers are rounded to four decimals for display only, so converting there and back returns the starting amount.
How to use the Ounces to Cups Calculator
- Type the amount of ounces, or of cups if you are going the other way.
- Choose fluid ounces for liquids or ounces by weight for dry ingredients.
- For weight, choose the ingredient so a density is available.
- Read the cups, fluid ounces, tablespoons and, for weight, grams.
- Open Show the work to follow each step, or use Copy, Print or Share.
Worked example
A recipe asks for 8 ounces by weight. For all-purpose flour that is 226.8 g, or 1.89 cups, while 8 fluid ounces of any liquid is exactly 1 cup.
| Ingredient | Grams per cup | Cups in 8 oz |
|---|---|---|
| All-purpose flour | 120 | 1.89 |
| Granulated sugar | 198 | 1.1454 |
| Butter | 226 | 1.0035 |
| Water | 227 | 0.9991 |
| Honey | 336 | 0.675 |
Frequently asked questions
How many cups is 8 ounces?
If they are fluid ounces, 8 ounces is exactly 1 US cup. If it is weight, the answer depends on the ingredient: about 1.89 cups of flour or 0.675 cups of honey.
Are fluid ounces and ounces the same?
No. A fluid ounce is a unit of volume, about 29.57 mL, while an ounce of weight is about 28.35 g. They are only close to equal for water.
How many ounces are in a cup?
A US cup holds 8 fluid ounces. By weight it depends on what is in it, for instance about 4.2 ounces of all-purpose flour or 11.9 ounces of honey.
Why does the calculator ask me to choose an ingredient?
Ounces by weight cannot become cups without knowing how heavy the ingredient is per cup. The calculator asks rather than guessing.
Does this work for UK or metric cups?
No. It uses the US customary cup of 236.588 mL only. For milliliters and other units, try the cooking measurement converter.