What packed means
Spoon brown sugar into the cup and press it firmly enough to remove large air gaps. Add more, press again, and level the top when the cup is full. The sugar should hold the cup's shape when turned out.
Do not use the word packed for a loose cup. Packing pressure, moisture, clumping, and brand can change the mass, which is why the condition belongs beside the number.
Why sources vary
King Arthur Baking groups light and dark brown sugar together at 213 g per packed US cup. A USDA FoodData Central record as displayed by MyFoodData lists 220 g packed and 145 g unpacked. Doves Farm gives 180 g for a brown-sugar cup but does not specify packing in that row.
These are reference conventions, not a universal physical constant. PantryGauge does not average them into a made-up value; it shows the chosen source and the conditions attached to it.
Use a scale for a repeatable bake
If a recipe gives a weight, weigh the sugar. If it gives a packed cup, follow that recipe's method. For a different cup system, check the recipe country and use the matching volume convention before converting.
Questions readers ask
How many grams are in 1 cup of packed brown sugar?
This page uses King Arthur Baking's reference: 1 US cup of packed light or dark brown sugar is 213 g.
Is 1 cup of brown sugar always 213 g?
No. Published references vary and unpacked sugar is lighter. The packing method, source convention, moisture, and cup system must be stated.
How much is ½ cup packed brown sugar?
Using the 213 g reference, ½ cup is about 107 g. It is a derived estimate, so keep the packed qualifier visible.
Can I use the same number for loose brown sugar?
No. Loose or unpacked brown sugar occupies more volume for the same mass. Use the recipe's stated method or weigh it.
Sources and method
Numerical answers are tied to the stated ingredient, state, cup convention, and source. Derived values are calculated from the cited reference and rounded for kitchen use.