Dry ounces vs. fluid ounces
1 cup = 8 fl oz
by volume, always. By weight it depends: flour 4.23 oz · sugar 6.98 oz · water 8.3 oz
Converter
Other cup standards
US cups: 1 · nutrition-label cups (240 mL): 0.986 · metric cups (250 mL): 0.946 · UK fluid ounces: 8.33
The word ounce covers two different measurements. A fluid ounce is volume, the space an ingredient fills, and it is what measuring cups and spoons read. The ounce on a scale is the avoirdupois ounce, a unit of weight equal to 28.35 g, sixteen to the pound. A recipe that lists "8 oz chocolate" wants weight; one that lists "8 fl oz milk" wants a cup.
The two line up only for water and liquids close to it. One fl oz of water weighs about 1.04 oz, so a cup of water reads near 8.3 oz on a scale. Flour has a lot of air between its particles, so a cup weighs about 4.25 oz, while dense honey weighs close to 12 oz per cup. That spread is why the chart below gives weight per cup one ingredient at a time.
| Ingredient | 1 cup | 1/2 cup | 1/3 cup | 1/4 cup | How measured |
|---|---|---|---|---|---|
| Water | 236 g · 8.32 oz | 118 g · 4.16 oz | 79 g · 2.77 oz | 59 g · 2.08 oz | liquid measuring cup |
| Milk | 227 g · 8.01 oz | 114 g · 4 oz | 76 g · 2.67 oz | 57 g · 2 oz | liquid measuring cup |
| All-purpose flour | 120 g · 4.23 oz | 60 g · 2.12 oz | 40 g · 1.41 oz | 30 g · 1.06 oz | spooned into the cup and leveled |
| Bread flour | 120 g · 4.23 oz | 60 g · 2.12 oz | 40 g · 1.41 oz | 30 g · 1.06 oz | spooned and leveled |
| Whole wheat flour | 113 g · 3.99 oz | 57 g · 1.99 oz | 38 g · 1.33 oz | 28 g · 1 oz | spooned and leveled |
| Granulated sugar | 198 g · 6.98 oz | 99 g · 3.49 oz | 66 g · 2.33 oz | 50 g · 1.75 oz | scooped and leveled |
| Brown sugar (packed) | 213 g · 7.51 oz | 107 g · 3.76 oz | 71 g · 2.5 oz | 53 g · 1.88 oz | packed firmly |
| Powdered (confectioners') sugar | 113 g · 3.99 oz | 57 g · 1.99 oz | 38 g · 1.33 oz | 28 g · 1 oz | spooned and leveled |
| Butter | 227 g · 8 oz | 113 g · 4 oz | 76 g · 2.67 oz | 57 g · 2 oz | cut at the Tbsp marks on the wrapper (1 stick = 1/2 cup) |
| Vegetable oil | 198 g · 6.98 oz | 99 g · 3.49 oz | 66 g · 2.33 oz | 50 g · 1.75 oz | liquid measuring cup |
| Honey | 336 g · 11.85 oz | 168 g · 5.93 oz | 112 g · 3.95 oz | 84 g · 2.96 oz | greased cup |
| Maple syrup | 312 g · 11.01 oz | 156 g · 5.5 oz | 104 g · 3.67 oz | 78 g · 2.75 oz | liquid measuring cup |
| Rolled oats | 89 g · 3.14 oz | 45 g · 1.57 oz | 30 g · 1.05 oz | 22 g · 0.78 oz | scooped and leveled |
| Long-grain rice (dry) | 198 g · 6.98 oz | 99 g · 3.49 oz | 66 g · 2.33 oz | 50 g · 1.75 oz | scooped and leveled |
| Chocolate chips | 170 g · 6 oz | 85 g · 3 oz | 57 g · 2 oz | 43 g · 1.5 oz | scooped and leveled |
| Cocoa powder (unsweetened) | 84 g · 2.96 oz | 42 g · 1.48 oz | 28 g · 0.99 oz | 21 g · 0.74 oz | spooned and leveled |
| Peanut butter | 270 g · 9.52 oz | 135 g · 4.76 oz | 90 g · 3.17 oz | 68 g · 2.38 oz | packed |
| Shredded cheese | 113 g · 3.99 oz | 57 g · 1.99 oz | 38 g · 1.33 oz | 28 g · 1 oz | loosely filled |
Why packages list weight
US food packages state their net contents. Solid and dry foods are usually labeled by net weight in ounces and grams, while liquids such as milk, juice and oil are usually labeled in fluid ounces. Weight is the dependable figure for solids because their volume changes with how they settle in the bag or can. So the ounces on a can of tomatoes or a bag of chocolate chips say nothing direct about cups. Pages like 15 oz to cups and 14 oz to cups give the practical volume for common cans.
Dry measuring cups vs. liquid measuring cups
A 1-cup dry measure and the 1-cup line on a liquid measure hold the same volume. Dry cups are made to be filled to the rim and leveled; liquid cups leave room above the top line so you can carry them without spilling. Neither one turns volume into weight. If a recipe gives ounces for a dry ingredient, a kitchen scale is the only tool that measures it directly.
Converting dry ounces to cups
- Find the ingredient in the chart below and note its grams per cup.
- Convert the recipe's ounces to grams (1 oz = 28.35 g).
- Divide by the grams per cup, then round to a measure you own.
For example, 8 oz of all-purpose flour is about 227 g, and 227 divided by 120 g per cup is about 1.89 cups, a little under 2 cups.
Questions
Are dry ounces and fluid ounces the same?
No. Fluid ounces measure volume and dry ounces measure weight. They come close only for water, where 1 fl oz weighs about 1.04 oz.
How many cups is 8 dry ounces?
It depends on the ingredient: 8 oz by weight is a little under 2 cups of all-purpose flour, a little over 1 cup of granulated sugar and about 1 1/3 cups of chocolate chips.
Can I use a liquid measuring cup for flour?
You can, but it is hard to level, so the amount tends to run high. A dry cup filled with a spoon and leveled matches the weights in the chart.
Sources: US customary units: NIST Handbook 44 · ingredient weights: King Arthur Baking ingredient weight chart. How we calculate.