Measuring flour and reading reference weights

Last reviewed 2026-11-03

Flour is the ingredient where cups and grams disagree most often. It's light, it compresses easily, and different sources measure it in different ways.

Published figures don't agree

USDA records the measuring method for these as "undetermined", and King Arthur's chart doesn't state one either, so we can't say exactly why they differ. What it does show is that "a cup of flour" is not one fixed weight.

Which figure should you use?

• The recipe's own weight, if it gives one. That's the amount the author used.
• The recipe author's measuring method, if they describe one. Many recipe writers say how they fill the cup.
• Otherwise, a reference figure is a reasonable estimate. The cups to grams converter shows USDA's figure and King Arthur's side by side.

Measuring with cups

How you fill the cup changes the weight. Scooping the cup straight into the bag presses flour down, so the cup holds more. Spooning flour lightly into the cup and levelling it with a straight edge packs it less. The same pattern shows up in USDA's figures for powdered sugar: sifted is 100 g a cup, unsifted 120 g.

Whichever way you measure, do it the same way every time, and the same way as the recipe author if you know it.

Measuring with a scale

A kitchen scale removes most of the guesswork. Put the bowl on the scale, set it to zero, and add flour until you reach the weight. It's also faster for scaled recipes, because odd amounts like 0.3 cup are no harder to weigh than a full cup.