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How we measure
Every cup weight on this site comes from USDA FoodData Central (49 of 53 ingredients) or, where USDA has no figure, from King Arthur Baking's ingredient weight chart. Each ingredient page names the exact USDA food and links to it.
The sources
USDA FoodData Central (SR Legacy). The US Department of Agriculture's food composition database lists measured portion weights for thousands of foods, such as "1 cup = 125 g" for all-purpose flour. The data is public domain. We match each ingredient to one USDA food by hand (for example, rolled oats to "Cereals, oats, regular and quick, dry", not to whole oat groats) and use the portion USDA measured.
King Arthur Baking. King Arthur's ingredient weight chart is the most used reference among American bakers. We show its figure on every ingredient page for comparison and credit it there. Its cups are usually a little lighter than USDA's because King Arthur fills cups more gently, and it rounds liquids to 8 oz (227 g) per cup.
Cup and spoon sizes
| Measure | ml | Equals |
|---|---|---|
| US cup | 236.6 | 16 tbsp, 48 tsp, 8 fl oz |
| US tablespoon | 14.79 | 3 tsp |
| US teaspoon | 4.93 | |
| US fluid ounce | 29.57 | 2 tbsp |
| Metric cup (UK, AU, NZ, CA) | 250 | 8.45 US fl oz |
| Metric tablespoon | 15 | Australia: 20 ml |
| Metric teaspoon | 5 |
How the converter rounds
Answers show three significant figures and the nearest combination of standard US cups (¼, ⅓, ½, ⅔, ¾), tablespoons and teaspoons. When no combination is within 2%, the answer says "scant" (fill slightly short) or "heaping" (slightly over). For anything where accuracy matters, such as bread and macarons, use the gram weight and a scale.
Corrections
Spotted a weight that doesn't match your kitchen? Tell us with the brand and how you filled the cup, and we will check it against the sources.