Quick answer: A cup holds 8 fluid ounces of liquid, but ounces of weight depend on the ingredient: a cup of flour is about 4 1/4 oz, sugar about 7 oz, and butter 8 oz. Use fluid ounces for liquids and a scale for dry goods.
Short answer: a U.S. cup holds 8 fluid ounces of liquid. For dry ingredients, ounces measure weight, so the answer depends on what you are measuring: a cup of flour is about 4 1/4 oz, a cup of sugar about 7 oz, and a cup of butter 8 oz. Use the grocery & cooking unit converter when you need an exact number for a specific ingredient.
Most conversion mistakes in the kitchen come from mixing up fluid ounces (volume) and ounces (weight). Once you separate those two, the rest is easy arithmetic, and the charts below cover almost every conversion you will meet while cooking or comparing grocery prices.
Ounces to cups: the quick answer for liquids
For milk, water, juice, broth, and oil, fluid ounces convert cleanly to cups.
| Fluid ounces | Cups | Tablespoons | Milliliters (approx.) |
|---|---|---|---|
| 1 fl oz | 1/8 cup | 2 tbsp | 30 mL |
| 2 fl oz | 1/4 cup | 4 tbsp | 59 mL |
| 4 fl oz | 1/2 cup | 8 tbsp | 118 mL |
| 6 fl oz | 3/4 cup | 12 tbsp | 177 mL |
| 8 fl oz | 1 cup | 16 tbsp | 237 mL |
| 12 fl oz | 1 1/2 cups | 24 tbsp | 355 mL |
| 16 fl oz | 2 cups (1 pint) | 32 tbsp | 473 mL |
| 32 fl oz | 4 cups (1 quart) | 64 tbsp | 946 mL |
| 64 fl oz | 8 cups (1/2 gallon) | 128 tbsp | 1.9 L |
| 128 fl oz | 16 cups (1 gallon) | 256 tbsp | 3.8 L |
The official factor behind these numbers: 1 fluid ounce is 29.5735 milliliters, and 1 gallon is 3.785 liters, according to the National Institute of Standards and Technology (NIST).
Fluid ounces vs ounces: why “8 oz = 1 cup” is only half true
- Fluid ounce (fl oz) measures how much space a liquid takes up. A measuring cup shows these.
- Ounce (oz) measures weight. A kitchen scale shows these.
Water and milk happen to weigh close to 8 ounces per cup, so the two seem interchangeable for liquids. They are not interchangeable for dry goods. A cup of flour fills the same space as a cup of water, yet it weighs roughly half as much. That is why a recipe that asks for “8 oz of flour” is about 1 7/8 cups, not 1 cup.
On packages, solid foods use weight (oz, lb, g) and liquids use fluid ounces (fl oz, mL, L). If you are comparing a 12 oz bag of pasta with a 16 fl oz bottle of sauce, you are comparing weight to volume, so be careful about which price per unit you use.
Ingredient weight chart: cups to ounces and grams
These are typical weights for 1 U.S. cup. Real values vary with brand, humidity, and how you scoop, so treat them as planning numbers. The weights for flour, brown sugar, butter, and honey follow the King Arthur Baking ingredient weight chart, and the other figures match the converter tool.
| Ingredient (1 cup) | Ounces (weight) | Grams (approx.) |
|---|---|---|
| Water | 8.3 oz | 237 g |
| Milk | 8.6 oz | 245 g |
| All-purpose flour | 4 1/4 oz | 120 g |
| Granulated sugar | 7 oz | 200 g |
| Brown sugar (packed) | 7 1/2 oz | 213 g |
| Powdered sugar | 4 to 4 1/4 oz | 113 to 120 g |
| Butter | 8 oz | 227 g |
| Vegetable oil | 7.7 oz | 218 g |
| Honey | 12 oz | 339 g |
| Uncooked white rice | 6.5 oz | 185 g |
| Rolled oats | 3.2 oz | 90 g |
| Shredded cheddar | 4 oz | 113 g |
| Chocolate chips | 6 oz | 170 g |
Why flour is the tricky one: scooping a measuring cup straight into the bag packs the flour, so a “cup” can weigh 140 grams or more instead of 120. Spooning flour into the cup and leveling it gets closer to 120 grams. A scale removes the guessing, and most baking sites recommend weighing flour for that reason.
How many cups are in a pound?
Divide 454 grams by the grams per cup.
| Ingredient | Cups per 1 lb |
|---|---|
| All-purpose flour | about 3.8 cups |
| Granulated sugar | about 2.3 cups |
| Brown sugar (packed) | about 2.1 cups |
| Butter | 2 cups |
| Water | about 1.9 cups |
| Uncooked white rice | about 2.5 cups |
| Rolled oats | about 5 cups |
Cups, tablespoons, and teaspoons
| Measure | Equals |
|---|---|
| 3 teaspoons | 1 tablespoon |
| 1 tablespoon | 1/2 fluid ounce, about 15 mL |
| 4 tablespoons | 1/4 cup |
| 5 tablespoons + 1 teaspoon | 1/3 cup |
| 8 tablespoons | 1/2 cup |
| 10 tablespoons + 2 teaspoons | 2/3 cup |
| 12 tablespoons | 3/4 cup |
| 16 tablespoons | 1 cup |
| 48 teaspoons | 1 cup |
Butter shortcut: one stick of butter is 4 oz, 1/2 cup, or 8 tablespoons. Most butter packages print tablespoon lines on the wrapper, so you can cut the exact amount without dirtying a measuring cup.
Pounds, ounces, and grams
| Weight | Ounces | Grams |
|---|---|---|
| 1/4 lb | 4 oz | 113 g |
| 1/2 lb | 8 oz | 227 g |
| 3/4 lb | 12 oz | 340 g |
| 1 lb | 16 oz | 454 g |
| 2 lb | 32 oz | 907 g |
| 5 lb | 80 oz | 2.27 kg |
| 1 kg | 35.3 oz | 2.2 lb |
| 100 g | 3.5 oz | 0.22 lb |
NIST defines 1 pound as exactly 453.59237 grams, which is where these numbers come from.
Pints, quarts, and gallons
| Unit | Cups | Fluid ounces | Liters |
|---|---|---|---|
| 1 pint | 2 | 16 | 0.47 |
| 1 quart | 4 | 32 | 0.95 |
| 1/2 gallon | 8 | 64 | 1.89 |
| 1 gallon | 16 | 128 | 3.79 |
| 1 liter | about 4.2 | 33.8 | 1 |
Be careful with UK recipes: an imperial pint is about 568 mL (20 imperial fluid ounces), so it is larger than a U.S. pint at 473 mL.
Oven and food-safety temperatures
Subtract 32, then multiply by 5/9.
| Fahrenheit | Celsius | Common use |
|---|---|---|
| 40°F | 4°C | Refrigerator maximum |
| 140°F | 60°C | Keep hot food at or above |
| 145°F | 63°C | Whole cuts of beef, pork, lamb (USDA) |
| 165°F | 74°C | Poultry and leftovers (USDA) |
| 325°F | 163°C | Slow roasting |
| 350°F | 177°C | Most baking (ovens often show 180°C) |
| 375°F | 191°C | Roasting vegetables |
| 400°F | 204°C | Crisping, sheet-pan dinners |
| 425°F | 218°C | Pizza, high heat roasting |
Why conversions matter for your grocery bill
Conversions are not only for cooking. They save money in the store too.
- Compare unit prices. A 24 oz jar at $4.99 costs about 21 cents per ounce ($0.208), or about $3.33 per pound. Convert every package to the same unit before comparing, or use the unit price calculator. The guide on unit price explained covers the full method.
- Cost out a recipe. Two cups of flour is about 240 grams. If a 5 lb bag (2,268 g) costs $3.49, that flour costs about $0.37. A recipe that uses 6 tablespoons of butter from a $4.50 pound (4 sticks) uses 3/4 of a stick, about $0.84. The recipe cost calculator automates this.
- Buy the right amount. A recipe that calls for 3 cups of shredded cheese needs about 12 oz of cheese (3 cups at 4 oz each), so an 8 oz bag is not enough. For more on turning recipes into shopping lists, see how to turn any recipe into a grocery list.
- Scale for a crowd. The party food calculator and the guide on how much turkey per person work in pounds, so a pounds-to-ounces refresher helps when you shop deli counters.
Metric and nutrition label differences
- Nutrition labels round. The FDA says that on nutrition labels, 1 teaspoon means 5 mL, 1 tablespoon means 15 mL, 1 cup means 240 mL, and 1 fluid ounce means 30 mL. The real U.S. cup is a little smaller, about 237 mL, so a label’s “1 cup” can differ from your measuring cup by about 1 percent.
- Metric cups differ. Recipes from Australia, New Zealand, and some other countries use a 250 mL cup and a 15 to 20 mL tablespoon. If a recipe is not American, check the units before you measure.
Quick cheat sheet to save
- 8 fl oz = 1 cup = 16 tablespoons = 48 teaspoons
- 2 cups = 1 pint, 4 cups = 1 quart, 16 cups = 1 gallon
- 16 oz = 1 pound, 4 oz = 1 stick of butter = 1/2 cup
- 1 oz = 28.35 g, 1 lb = 454 g, 1 kg = 2.2 lb
- 1 cup flour is about 120 g, 1 cup sugar about 200 g
- 350°F = 177°C
Limits of these numbers
Ingredient weights are approximations. Brands, humidity, packing, and how you scoop all change them. For baking, weigh dry ingredients if you can. The converter on this site uses typical values and labels them as estimates.
Sources
- National Institute of Standards and Technology, Special Publication 811: Guide for the Use of the International System of Units
- U.S. Food and Drug Administration, Guidance for Industry: Guidelines for Determining Metric Equivalents of Household Measures
- King Arthur Baking, Ingredient Weight Chart
- USDA Food Safety and Inspection Service, Leftovers and Food Safety (safe cooking temperatures)
Last reviewed October 7, 2026.
Evergreen method
Compare usable cost, not package price
The durable comparison is price per common unit adjusted for the share you will actually use.
Formula
usable unit cost = price ÷ (quantity × usable share)Reproducible steps
- 1.Convert every option to the same unit.
- 2.Estimate the share your household will use before spoilage.
- 3.Choose the lower usable unit cost only if storage and cash flow also work.
Put it to work
Run the numbers for your household
FAQ
Common questions
How many ounces are in a cup?
A U.S. cup holds 8 fluid ounces of liquid. For dry ingredients, ounces measure weight, so the answer changes: a cup of all-purpose flour weighs about 4 1/4 ounces, granulated sugar about 7 ounces, and butter 8 ounces.
Is an ounce the same as a fluid ounce?
No. A fluid ounce measures volume (space), and an ounce measures weight. Eight fluid ounces of water weigh about 8.3 ounces, but 8 fluid ounces of flour weigh only about 4 1/4 ounces. Package labels list weight in oz and liquids in fl oz.
How many cups are in a pound?
It depends on the ingredient. A pound is about 3.8 cups of all-purpose flour, 2.3 cups of granulated sugar, 2 cups of butter, and 1.9 cups of water. Use the weight on the package and a kitchen scale for accuracy.
How many tablespoons are in a cup?
There are 16 tablespoons in 1 cup. That makes 1/2 cup 8 tablespoons, 1/3 cup 5 tablespoons plus 1 teaspoon, and 1/4 cup 4 tablespoons. There are also 3 teaspoons in 1 tablespoon, or 48 teaspoons in a cup.
How many ounces are in a stick of butter?
A stick of butter weighs 4 ounces. It equals 1/2 cup, 8 tablespoons, or about 113 grams. A 1 pound package has 4 sticks, which equals 2 cups of butter.
How many ounces are in a pound?
There are 16 ounces in 1 pound. A half pound is 8 ounces, a quarter pound is 4 ounces, and 1 pound is about 454 grams. That is the conversion used for unit prices, such as price per ounce versus price per pound.
How many grams are in an ounce?
One ounce of weight is 28.35 grams, so 100 grams is about 3.5 ounces and 1 kilogram is about 35.3 ounces or 2.2 pounds. For quick math, round to 28 grams per ounce.
How many cups are in a quart, half gallon, and gallon?
A quart is 4 cups (32 fluid ounces), a half gallon is 8 cups (64 fluid ounces), and a gallon is 16 cups (128 fluid ounces). A pint is 2 cups, so a quart is 2 pints.
Is a U.S. cup the same as a metric cup?
Not exactly. A U.S. customary cup is about 237 mL, nutrition labels in the U.S. round a cup to 240 mL, and a metric cup used in some countries is 250 mL. The difference is small for most recipes but can matter in baking.
How do I convert Fahrenheit to Celsius for cooking?
Subtract 32 from the Fahrenheit temperature, then multiply by 5/9. So 350°F is about 177°C, 325°F is about 163°C, and the 165°F safe temperature for poultry is about 74°C. Many ovens round 350°F to 180°C.
Related
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How to Turn Any Recipe Into a Grocery List
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How Much Turkey Per Person? Chart, Thaw Times & Leftover Math (2026)
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