Why Global Bakers Are Ditching Cups and Ounces for Grams in 2026
The deepest source of failure in home baking stems from English vocabulary. The word "ounce" describes two fundamentally different physical properties: weight (mass) and fluid volume. A dry ounce measures gravitational pull on an ingredient. A fluid ounce measures the three-dimensional space a liquid occupies.
In the US customary system, one fluid ounce equals 29.57 milliliters. If you pour four fluid ounces of water into a glass, that liquid weighs roughly 118.3 grams, because water possesses a density of nearly one gram per milliliter. Pour four fluid ounces of vegetable oil, and the scale registers approximately 109 grams. Fill that same four-fluid-ounce vessel with packed all-purpose flour, and you might get 70 grams. Leave the flour aerated, and you might get 55 grams.
Conflating dry and fluid ounces produces structural disasters in the oven. When a cook sees "4 oz of sugar" and measures it inside a liquid measuring cup to the 4-ounce line, they introduce pure volume instead of mass. The culinary metric system eliminates this ambiguity completely. Grams always measure mass; milliliters always measure volume. There is no linguistic overlap to confuse a novice baker.