Why a cup of flour and a cup of honey are not the same weight

If a recipe gives cups and you want to use a scale, look for the author’s gram measurements first. If there are none, you need a conversion for the specific ingredient. One US cup of all-purpose flour is estimated here at 120 g; one US cup of honey at 340 g. Using the same weight for both would change the recipe substantially.

A cup measures space. Grams measure weight. The ingredient, how it is prepared and how it fills that space determine the conversion.

Start with the right ingredient

These are the estimates used in the site’s ingredient charts, per US customary cup. They are reference amounts, not measurements of your bag, brand or filled cup.

Ingredient	Approximate grams per US cup
Cocoa powder	84 g
Rolled oats	90 g
Almond flour	96 g
Cake flour	113 g
Powdered sugar	113 g
All-purpose flour	120 g
Rice, white and uncooked	195 g
Granulated sugar	198 g
Brown sugar, packed	213 g
Olive oil	216 g
Butter	227 g
Water	237 g
Whole milk	245 g
Honey	340 g

King Arthur Baking’s ingredient weight chart is a useful baking reference: it lists 120 g per cup for all-purpose flour and 198 g per cup for granulated sugar. It also distinguishes ingredients such as almond flour and almond meal. Similar names do not guarantee the same cup weight.

If your recipe supplies a different gram amount, follow that recipe’s measurement rather than replacing it with a general chart.

Scale the weight you looked up

For 1½ US cups of all-purpose flour, the site’s estimate gives 1.5 × 120 g = 180 g. For half a US cup of honey, it gives 0.5 × 340 g = 170 g.

You do not need a density formula to use the chart. Find the matching ingredient, then multiply its cup weight by the number of cups. Keep the cup standard the same throughout that calculation.

The per-ingredient pages provide charts for flour, granulated sugar, butter and honey, including common cup fractions.

Packing and sifting change what fits in the cup

Scooping flour straight from a compacted bag can put more flour into a cup than spooning it in loosely. Where the recipe specifies spoon-and-level, spoon the flour into the measure and sweep the top flat without pressing it down. Follow the author’s method when it differs.

The wording around preparation matters too. “One cup of sifted flour” asks you to sift before measuring. “One cup of flour, sifted” asks you to measure first. Packed brown sugar, loose brown sugar and sifted powdered sugar should not be treated as identical measurements.

A scale makes a stated weight repeatable. It cannot recover the author’s intended weight from an unclear cup measurement, so a converted quantity is still an estimate.

Check the cup before converting

A US customary cup holds about 237 ml. A metric cup holds 250 ml. US nutrition labelling uses 240 ml under 21 CFR §101.9. Check the recipe’s measuring notes rather than relying only on its country.

With the same ingredient and filling method, a 250 ml cup holds about 6% more than a US customary cup. Using the flour estimate above, that is roughly 127 g rather than 120 g. This matters when some ingredients are measured in cups and others, such as butter, already have fixed weights.

Choose the converter for the measurement you have

The kitchen converter converts volumes: cups, millilitres, decilitres, spoons and fluid ounces. It does not turn an ingredient’s cups into grams. Use the ingredient charts for that estimate, or the recipe’s own weights when available.

When weighing, put the empty bowl on the scale and zero it before adding the ingredient. Record the weight you actually used alongside the recipe; that makes the same measurement easier to repeat next time.

Last reviewed 2 October 2026.