Is 28 Grams in One Cup? Understanding Weight vs. Volume in Cooking

November 28, 2025 •

3 min read

Did you know that one cup of flour can weigh up to 30% more than another, depending on how it's measured? The simple answer to 'Is 28 grams in one cup?' is no, because the conversion from weight (grams) to volume (cups) is not universal and varies by ingredient.

Quick Summary

This guide clarifies the fundamental differences between measuring ingredients by weight versus volume. It explores why conversions vary based on ingredient density and provides practical examples for common items. The article also explains why weight-based measurements lead to more consistent results.

Key Points

Weight vs. Volume: A cup measures volume (space), while a gram measures weight (mass). Their conversion is not fixed.
Density is Key: The density of an ingredient determines how many grams are in a cup. Lighter ingredients like flour weigh less than denser ones like sugar for the same volume.
28 Grams Varies: 28 grams is not one cup for any typical ingredient. For example, it's 1/8 cup of butter, but 1/3 cup of rolled oats.
Baking Requires Precision: In baking, accurate measurements are critical for recipe success. Volume measuring introduces inconsistency due to factors like packing.
Use a Kitchen Scale: For the most accurate and consistent results, always measure your ingredients by weight using a kitchen scale.
Proper Measuring Technique: If using cups, use the 'spoon and sweep' method for dry goods and ensure liquid measurements are read at eye level on a flat surface.
Regional Differences: Be aware that standard cup sizes (US vs. Metric) can vary by country, further complicating volumetric conversions.

Weight vs. Volume: Why You Can't Convert Without Density

The most common mistake cooks and bakers make is assuming that a cup is a consistent measurement regardless of the ingredient. While a cup is a fixed unit of volume—the amount of space an ingredient occupies—a gram is a unit of weight, or mass. The relationship between volume and weight is defined by the ingredient's density. This is why a cup of fluffy, sifted flour weighs significantly less than a cup of dense, packed brown sugar. To accurately convert a specific weight like 28 grams to a volume like a cup, you must know the ingredient's density.

The Importance of a Kitchen Scale

For any recipe that requires precision, especially in baking, a kitchen scale is the most reliable tool. Weighing ingredients in grams eliminates the inconsistencies that arise from volumetric measurements. For example, a recipe calling for '1 cup of flour' can yield wildly different results depending on whether the baker scoops and levels the flour or spoons it into the cup. Using a scale ensures your ingredient ratio is consistent every time, leading to more predictable and delicious outcomes.

Specific Ingredient Conversions for 28 Grams

To illustrate the density problem, let's look at what 28 grams equals for various common ingredients. The phrase '28 grams in one cup' is misleading because for most items, 28 grams is only a fraction of a cup. The only instance where a weight to cup conversion is fairly standard is for water, where 1 milliliter (a unit of volume) weighs 1 gram. But even then, regional differences in standard cup size can cause discrepancies.

Here are some concrete examples of what 28 grams looks like in a cup measurement for different ingredients:

Butter: 28 grams is precisely 1/8 cup (or 2 tablespoons), as one stick of butter (113 grams) equals 1/2 cup.
Rolled Oats: 28 grams of rolled oats is approximately 1/3 cup.
Granulated Sugar: 28 grams of granulated sugar is roughly 1/8 cup, as one cup weighs around 200 grams.
All-Purpose Flour: 28 grams is just under 1/4 cup. One cup of all-purpose flour typically weighs around 120-130 grams.
Cocoa Powder: For cocoa powder, 28 grams is about 1/3 cup, since one cup of cocoa powder weighs around 82-100 grams depending on brand and packing.

How to Measure Accurately Without a Scale

While a scale is the gold standard for accuracy, if you must use measuring cups, follow these best practices to ensure consistency:

For dry, powdery ingredients (flour, cocoa powder): Use the 'spoon and sweep' method. Spoon the ingredient lightly into the measuring cup until it's overflowing. Then, use a flat-edged utensil like a butter knife to sweep the excess off the top. Never tap the cup or pack the ingredient, as this will result in a denser, heavier measurement than intended.
For brown sugar: This is the exception. Brown sugar should be packed firmly into the measuring cup until it holds its shape when turned out.
For liquids: Place the liquid measuring cup on a level surface and read the measurement at eye level to avoid a parallax error.

Grams to Cups Conversion Table for 28 Grams

To provide a clearer picture, here is a comparison table for different ingredients to convert 28 grams to cups:


Ingredient	28 Grams is Approximately...
Butter	1/8 cup (2 tablespoons)
Rolled Oats	1/3 cup
All-Purpose Flour	Just under 1/4 cup
Granulated Sugar	Just over 1/8 cup
Brown Sugar (packed)	About 2 tablespoons
Cocoa Powder	About 1/3 cup
Water	1/8 cup

Conclusion: Precision Over Estimation

In conclusion, the weight of an ingredient in a standard measuring cup is not fixed, making the idea that 28 grams equals one cup a complete myth. Your specific ingredient and its density dictate the conversion, not a universal rule. For consistent and reliable results, particularly in baking where chemical reactions demand precision, a kitchen scale is the superior tool. However, understanding the correct volumetric measurement techniques can help when a scale isn't available. Ultimately, investing a little time in learning these conversion principles can significantly improve your cooking and baking outcomes.

King Arthur Baking's Ingredient Weight Chart provides a great reference for accurate conversions.

Frequently Asked Questions

Because a measuring cup measures volume, and different ingredients have different densities. A cup of a light ingredient like flour weighs far less than a cup of a dense ingredient like butter, making volume an inconsistent way to measure by weight.

Yes, measuring by weight with a kitchen scale is the most accurate method. It removes inconsistencies caused by packing, sifting, or leveling ingredients, ensuring your recipe results are consistent every time.

Density in cooking refers to how much mass an ingredient has per unit of volume. A denser ingredient (like honey) will weigh more in a cup than a less dense ingredient (like cocoa powder).

No, 28 grams is not a cup of water. Since water has a density close to 1 gram per milliliter, 28 grams of water is approximately 28 milliliters, which is equal to about 1/8 of a US customary cup.

Recipes often list both measurements to cater to different cooking styles and ensure accuracy. Using grams is for precise measurement, while cups offer a quicker, though less exact, volume-based method.

To measure flour correctly, use the 'spoon and sweep' method. Spoon flour lightly into the measuring cup until overflowing, then level the top with a straight edge. This prevents overpacking and ensures a more consistent measurement.

For accurate conversions, yes. Since each ingredient has a unique density, a specific conversion chart is needed. However, using a kitchen scale in grams eliminates the need for these charts for each item.