Cooking Measurement Converter
Cups to grams for the ingredient you're actually using, because a cup of flour and a cup of honey differ by nearly three times.
In short
A cup measures volume, not weight, so the conversion depends entirely on the ingredient. One US cup is 125 g of flour, 200 g of sugar and 340 g of honey. Weighing is the only reliable method for baking.
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Why cups cause so much trouble
A cup measures volume. Recipes need mass. Those are only the same thing if the density is constant, and it isn't, not between ingredients, and not even for the same ingredient measured twice.
| One US cup of… | Weighs |
|---|---|
| Rolled oats | 90 g |
| Cocoa powder | 85 g |
| Plain flour | 125 g |
| Granulated sugar | 200 g |
| Butter | 227 g |
| Water | 237 g |
| Honey | 340 g |
A cup of honey weighs nearly four times a cup of oats. Any conversion that doesn't ask what's in the cup is not a conversion.
The flour problem specifically
Flour is compressible, which makes it the worst offender. Depending on how it gets into the cup:
- Spooned and levelled: 120–125 g. The method most recipes assume.
- Scooped from the bag: 140–150 g. The method most people actually use.
- Sifted first: 110–115 g.
That's a spread of up to 30%. In bread it changes the hydration and the dough won't come together. In cakes it's the difference between moist and dry. It's why professional recipes are written in grams and why every serious baking book has switched.
Cups are not the same size everywhere
| Measure | US | Metric (UK/AU/NZ) | Old imperial |
|---|---|---|---|
| Cup | 240 ml | 250 ml | 284 ml |
| Tablespoon | 15 ml | 15 ml (AU: 20 ml) | 17.7 ml |
| Teaspoon | 5 ml | 5 ml | 5.9 ml |
| Fluid ounce | 29.57 ml | 28.41 ml | 28.41 ml |
| Pint | 473 ml | 568 ml | 568 ml |
The Australian tablespoon is the sneaky one: at 20 ml it's a third larger than everyone else's. In a recipe calling for three tablespoons of a strong ingredient, that's a noticeable error.
Ounces and fluid ounces are different things
Ounces measure weight; fluid ounces measure volume. They coincide only for water, because water happens to weigh about one ounce per fluid ounce.
So "8 oz of flour" means 227 g on a scale, while "8 fl oz of milk" means about 240 ml in a jug. Recipes usually rely on context to distinguish them, which works right up until it doesn't.
Fan ovens run hot
A fan circulates air, so heat reaches the food faster. The standard adjustment is 20°C lower (about 35°F) than a conventional recipe states, or keeping the temperature and cutting the time by roughly 10%.
Most published recipes give conventional temperatures unless they say otherwise. Ignoring the adjustment is the usual reason biscuits brown on the outside while staying raw in the middle. Ovens also lie: an oven thermometer often reveals a 15–20°C discrepancy from the dial.
Just buy a scale
A digital kitchen scale costs less than a couple of failed cakes. It's faster than measuring cups, you can tare between ingredients and use one bowl. More accurate, and it means any recipe in the world becomes usable without conversion.
Keep the cups for liquids and for things where precision doesn't matter. Use the scale for anything baked, where ratios genuinely decide the outcome.
Frequently asked questions
How many grams is a cup of flour?
About 125 g for plain white flour, if you spoon it into the cup and level it off. Scoop the cup straight into the bag and you can compact it to 150 g or more. A 20% difference that is enough to make a cake dry. This is the single strongest argument for weighing.
Why does the ingredient matter?
Because a cup measures volume, not weight, and ingredients have wildly different densities. A cup of flour is 125 g, a cup of granulated sugar 200 g, a cup of honey 340 g. Converting cups to grams without knowing what is in the cup is guesswork.
Is a US cup the same as a UK or Australian cup?
No. A US cup is 240 ml, a metric cup (UK, Australia, NZ) is 250 ml, and an old imperial cup was 284 ml. Australian tablespoons are 20 ml against 15 ml almost everywhere else. Small gaps, but they compound across a recipe.
What is the difference between fluid ounces and ounces?
Fluid ounces measure volume, ounces measure weight, and they are only interchangeable for water. Eight fluid ounces of honey weighs about 12 ounces. If a recipe says "8 oz flour" it means weight; "8 fl oz milk" means volume.
Do I need to adjust for a fan oven?
Yes, reduce the temperature by about 20°C (35°F), or shorten the time by roughly 10%. Fan ovens circulate air, so heat transfers faster. The conversion table below shows conventional, fan and gas mark side by side.