Cups to grams converter

A cup is a volume and a recipe wants a weight, so somewhere between the two a number has to be invented — and the people who publish those numbers do not agree. King Arthur Baking puts a cup of all-purpose flour at 120 g; the USDA puts the same cup at 125 g. On bread flour the gap widens to 120 g against 137 g, which is fourteen percent, and on brown rice flour it is 128 g against 158 g. Neither is wrong. A cup of flour weighs whatever the flour and the hand that filled it decide, and the two organisations measured different flour with different hands. So this page does not average them. It shows both figures, says which chart each came from, and tells you how far apart they are at the amount you are actually making. The list is short — twenty-one ingredients — because every one of them appears in both charts with a figure for a whole cup. Nothing here was filled in from memory to make the list longer.

How it is calculated

grams = grams per cup × cups

There is no arithmetic worth defending here; the multiplication is trivial and the whole question is which number you multiply by. Every figure on this page is transcribed from one of two documents: the King Arthur Baking ingredient weight chart, and the food_portion table of the USDA FoodData Central SR Legacy release, which records the gram weight of one household measure of a food. Where the USDA qualifies the measure — "cup unsifted, dipped" for cake flour, "cup packed" for brown sugar — the qualifier is printed next to the number, because it is part of what the number means.

Source: Grams scale with the number of cups, so every answer here is the chart figure for one cup multiplied by the amount asked for

Questions people ask

Which figure should I use?

If the recipe came from King Arthur, use the King Arthur column, and the same for anything written against USDA data. That is not a dodge: a recipe is a set of ratios that its author tested with their own cup, so the chart the author used is the one that reproduces their loaf. Where you have no idea, the gap is the thing to look at rather than the figure. Four percent on all-purpose flour will not decide a cake. Fourteen percent on bread flour, on a dough already balanced to the gram, will.

Why is a cup of water 227 g on one chart and 237 g on the other?

Because King Arthur's chart carries an ounce column, and for water, milk, buttermilk, yogurt, sour cream and cream it reads 8 — the number of fluid ounces in a cup — and its gram column is that 8 read as 8 ounces of weight, which is 227 g. The USDA measured the mass instead: a US cup is about 237 mL, water is close to one gram per millilitre, and 237 g is what a cup of it weighs. This is the one place on the page where the physics settles it. For the liquids, the USDA figure is the weight; the King Arthur figure is a convenient equivalence that keeps a recipe internally consistent as long as you use it for every liquid in that recipe.

Does it matter how I fill the cup?

More than the difference between the charts does, and the USDA table proves it without leaving the one source. It lists a cup of brown sugar at 220 g packed and 145 g unpacked — the same sugar, the same cup, a 52 percent difference. Powdered sugar is 100 g sifted against 120 g unsifted, and cake flour is recorded specifically as "unsifted, dipped", which is the heaviest way to fill a cup with flour and part of why that figure is the highest here. If you scoop the cup through the bag you will beat any chart on this page; spooning the flour in and levelling it off will fall below all of them.

Why are there only twenty-one ingredients?

Because that is how many appear in both documents with a figure for a whole cup. Plenty more are in one and not the other: King Arthur publishes almond flour, semolina and demerara sugar, the USDA publishes cornstarch, molasses and sesame seeds. Adding those would mean showing one column and inventing the other, or quietly dropping the comparison that is the reason this page exists. Butter and eggs are missing for the same reason: King Arthur gives butter per 8 tablespoons and eggs per egg, so neither has a cup figure to line up against the USDA one.

Is a cup the same everywhere?

No, and this page is about the US cup of roughly 237 mL, the one American recipes mean. A metric cup, used in Australia and New Zealand, is 250 mL — about six percent more, which lands on top of every difference described here. Both charts on this page are American, so both are working from the smaller cup, and neither figure will be right for a recipe written to the metric one.

Why not just weigh it?

You should, and that is the honest end of this page. A scale removes the cup, the packing, the chart and the argument in one move, which is why every serious baking book now prints grams first. This tool exists for the recipes that do not — the ones already in a notebook, in cups, that you would like to scale or halve without introducing a new error every time you do it.

Related tools