Gram to Cup

170 grams of brown sugar, packed to cups

170 g of brown sugar, packed is about 0.77 cups, which is roughly 3/4 cup or 12.36 tablespoons. That comes from 220 g per US cup. Firmly packed. Loose brown sugar drops to about 200 g a cup.

Measure170 g of brown sugar, packed
Cups0.77
Kitchen measure3/4 cup
Tablespoons12.36
Grams per cup used220 g

Brown sugar is the only common ingredient that recipes tell you to compress on purpose. The molasses coating makes it clump and trap air, so an unpacked cup can weigh 20 g less than a packed one. When a recipe says one cup of brown sugar, it almost always means firmly packed.

Result
0.83 cups
About 7/8 cup of all-purpose flour. 100 g is 3.53 oz by weight.
Assumes spoon-and-level. Scooped flour runs closer to 140 g a cup.

Questions

How many cups is 170 g of brown sugar, packed?
0.77 cups, or about 3/4 cup. That is worked out at 220 g per US cup, and a cup of brown sugar, packed can run 200 to 220 g depending on packing pressure.
How many tablespoons is 170 g of brown sugar, packed?
About 12.36 tablespoons, since one US cup is 16 tablespoons. For small amounts tablespoons are usually the more accurate measure to work with.
Why does 170 g give a different number of cups for other ingredients?
Because cups measure volume and grams measure weight. 170 g of brown sugar, packed is 0.77 cups at 220 g per cup, while the same 170 g of a denser or lighter ingredient fills a different amount of space.

Other amounts of brown sugar, packed

125 g140 g150 g160 g165 g175 g180 g185 g200 g215 g

See all brown sugar, packed conversions or 170 g of every other ingredient.