How We Calculate

Every number on gramstoocup.com comes from one weight per cup for each ingredient, the same formula and the same rounding rules. Here's exactly how it works.

The weights we use, and where they come from

Weight of 1 US cup (236.6 ml), 1 tablespoon and 1 teaspoon
Ingredient1 cup1 tbsp1 tspHow it's measuredSourceKing Arthur
All-purpose flour125 g7.8 g2.6 gspooned and leveledUSDA120 g
Granulated sugar200 g12.5 g4.2 gscooped and leveledUSDA198 g
Butter227 g14.2 g4.7 gpacked, softenedUSDA227 g
Brown sugar (packed)220 g13.8 g4.6 gfirmly packedUSDA213 g
Powdered sugar120 g7.5 g2.5 gunsifted, spooned and leveledUSDA113 g
Milk244 g15.3 g5.1 gliquid measuring cupUSDA227 g
White rice (uncooked)185 g11.6 g3.9 guncooked long-grain, leveledUSDA198 g
Honey339 g21.2 g7.1 gliquid measuring cupUSDA336 g
Water237 g14.8 g4.9 gliquid measuring cupDensity of water227 g
Rolled oats89 g5.6 g1.9 gold-fashioned, leveledKing Arthur89 g
Bread flour120 g7.5 g2.5 gspooned and leveledKing Arthur120 g
Cake flour120 g7.5 g2.5 gspooned and leveledKing Arthur120 g
Whole wheat flour120 g7.5 g2.5 gspooned and leveledUSDA113 g
Almond flour96 g6 g2 gspooned, not packedKing Arthur96 g
Coconut flour128 g8 g2.7 gspooned and leveledKing Arthur128 g
Cocoa powder (unsweetened)86 g5.4 g1.8 gsifted if lumpy, spooned and leveledUSDA84 g
Peanut butter256 g16 g5.3 gpressed in, leveledNutrition label (2 tbsp = 32 g)270 g
Chocolate chips170 g10.6 g3.5 gscooped and leveledKing Arthur170 g
Cream cheese227 g14.2 g4.7 gsoftened, pressed inKing Arthur227 g
Plain yogurt227 g14.2 g4.7 gstirred, leveledKing Arthur227 g

The formula

cups = grams ÷ grams per cup

grams = cups × grams per cup

Each ingredient has one weight per US cup, stored in a single data file. The converter, the charts, the guides and the answers in the text all read from that file, so the answer for 100 g of flour is the same on every page.

Where the weights come from

We use, in this order:

  1. USDA FoodData Central household measures. The US Department of Agriculture publishes the weight of a cup, tablespoon or teaspoon for thousands of foods.
  2. King Arthur Baking’s ingredient weight chart, for ingredients USDA doesn’t list in a useful form, such as bread flour, almond flour and old-fashioned oats.
  3. Physics, for water: 1 ml of water weighs 1 g, so a 236.6 ml cup weighs about 237 g.

The table above shows our figure, its source and King Arthur Baking’s figure side by side. The two sometimes differ by a few grams, mostly because King Arthur rounds to ounces and measures flour a little lighter. Where it matters, our pages mention both.

Units we use

  • US cup: 236.588 ml (the US customary cup).
  • Metric cup: 250 ml, used in Australia, Canada, New Zealand and the UK. The converter’s Metric option scales every weight by 250 ÷ 236.6.
  • Tablespoon: 1/16 cup, 14.8 ml. Teaspoon: 1/48 cup, 4.9 ml.
  • Butter stick: 113.4 g, a quarter of a 1 lb box.
  • Ounce: 28.35 g (weight ounce, not fluid ounce).

How we measure

Weights assume standard American methods: flour, powdered sugar and cocoa are spooned into the cup and leveled; granulated sugar, rice and oats are scooped and leveled; brown sugar is firmly packed; butter and other fats are pressed in and leveled; liquids are measured in a liquid measuring cup at eye level.

How results are rounded

  • Cup answers are rounded to the nearest fraction you can measure (¼, ⅓, ½, ⅔, ¾) plus the nearest ½ tablespoon or ½ teaspoon.
  • When rounding moves the answer by more than 3%, we say “about”.
  • “Measure it with” shows the combination of standard 1, ½, ⅓ and ¼ cups and spoons that comes closest with the fewest fills.
  • Gram answers are rounded to the nearest gram.

Limits

A cup measure is never as exact as a scale. Humidity, brand, grind and how firmly you fill the cup can change the weight by 5–10%, more for flour. For bread, macarons and anything else that depends on precise ratios, weigh your ingredients.

Found a mistake?

Email contact@gramstoocup.com with the page and the number. We check and correct errors, and update the “last reviewed” date on the page.

Written and checked by Food technologist · Diploma in Food Engineering (2020–2023)

Muhammad builds and maintains the converters on gramstoocup.com. He checks every weight-per-cup figure against USDA FoodData Central and King Arthur Baking's ingredient weight chart before it goes live.

Last reviewed · How we calculate