Cups to Grams: Why Baking by Volume Goes Wrong (and How to Convert)
An American recipe asks for 2 cups of flour. A European recipe asks for 250 g. If you have ever tried to convert one into the other and ended up with dense bread or runny cookies, the problem was probably not your oven. It was the cup.
This guide explains why volume and weight are not interchangeable, which “cup” a recipe means, and how much common baking ingredients actually weigh per cup.
Volume measures space, weight measures stuff
A cup is a measure of volume: how much space something takes up. A gram is a measure of mass: how much matter there is. The two only line up for one ingredient, water, where 1 millilitre weighs almost exactly 1 gram.
For everything else, the weight of a cup depends on the ingredient’s density and on how it was packed into the cup:
| Ingredient (1 US cup) | Approximate weight |
|---|---|
| Water or milk | 237 g |
| All-purpose flour (spooned and levelled) | 120 g |
| Granulated sugar | 200 g |
| Butter | 227 g |
| Honey or syrup | 340 g |
The same cup holds almost three times as much honey as flour by weight. That is why converting “1 cup = 237 g” for every ingredient gives such poor results.
The flour problem
Flour is the ingredient where volume measuring fails worst. Because it is light and compressible, the way you fill the cup changes the result:
- Spooned into the cup and levelled with a knife: about 120–125 g.
- Scooped directly from the bag: often 140–150 g, because scooping packs it down.
- Sifted before measuring: closer to 110 g.
That is a difference of up to 30 % for the same “1 cup”, enough to turn a tender cake into a dry one. Professional bakers weigh flour for exactly this reason. EveryUnit’s cup of flour to grams converter uses 120 g per cup, the spooned-and-levelled standard used by most American test kitchens.
Which cup does your recipe mean?
Not all cups are the same size, which adds a second layer of confusion:
| Cup | Volume | Used in |
|---|---|---|
| US customary cup | 236.6 mL | Most American recipes |
| US “legal” cup | 240 mL | US nutrition labels |
| Metric cup | 250 mL | Australia, New Zealand, Canada, South Africa |
| Imperial cup | 284 mL | Older British recipes |
The difference between a US cup and a metric cup is only about 5 %, which rarely matters for a single cup of liquid. It matters more when a recipe uses several cups of flour, or when an older British recipe uses the much larger imperial cup.
As a rule of thumb: a recipe from the United States uses US cups; a modern recipe from Australia or New Zealand uses metric cups; a modern British recipe will normally give grams.
Butter: sticks, cups and tablespoons
American butter is sold in sticks of 4 ounces, about 113 g, with tablespoon markings on the wrapper:
- 1 stick = ½ cup = 8 tablespoons ≈ 113 g
- 2 sticks = 1 cup ≈ 227 g
- 1 tablespoon ≈ 14 g
Use the stick of butter to grams converter for quick checks. Outside the US, butter usually comes in 250 g blocks, so one block is a little more than two sticks.
Sugar is more forgiving, mostly
Granulated sugar flows freely and does not compress much, so a cup weighs a fairly consistent 200 g. See the cup of sugar to grams converter.
Brown sugar is different: recipes usually ask for it “firmly packed”, which raises the weight to roughly 210–220 g per cup. Powdered (icing) sugar is very light, at around 120 g per cup, and like flour it varies a lot with how it is filled.
A simple way to convert a recipe
- Identify the cup from the recipe’s origin, as described above.
- Convert each dry ingredient separately using its own weight per cup. Never use a single cups-to-grams factor for everything.
- Convert liquids by volume (cups to millilitres). For water and milk, millilitres and grams are interchangeable.
- Round sensibly. 1 cup of flour is 120 g, not 120.0 g; kitchen scales measure in whole grams.
- Write the converted values on the recipe so you only do the work once.
Why weighing is worth it
A basic digital kitchen scale costs less than a set of good measuring cups, and it makes baking more consistent:
- You get the same amount of flour every time, regardless of how it was packed.
- You can measure straight into the mixing bowl and reset the scale to zero between ingredients, so there are fewer cups to wash.
- Scaling a recipe up or down is simple multiplication.
Volume measuring is perfectly fine for small amounts such as a teaspoon of baking powder or a pinch of salt. For the main dry ingredients, weight wins.
Key takeaways
- A cup measures volume, so its weight depends on the ingredient: about 120 g for flour, 200 g for sugar and 340 g for honey.
- Flour is the least reliable: scooping instead of spooning can add 20–30 %.
- US, metric and imperial cups are different sizes: 237, 250 and 284 mL.
- Convert each ingredient with its own factor, and weigh flour whenever you can.
The cooking ingredients converter covers cups, tablespoons, sticks and ounces for the most common baking ingredients.