Gram to Cup

90 grams of all-purpose flour to cups

90 g of all-purpose flour is about 0.75 cups, which is roughly 3/4 cup or 12 tablespoons. That comes from 120 g per US cup. Assumes spoon-and-level. Scooped flour runs closer to 140 g a cup.

Measure90 g of all-purpose flour
Cups0.75
Kitchen measure3/4 cup
Tablespoons12
Grams per cup used120 g

Flour is the ingredient where cup measuring goes wrong most often. It compresses easily, so the same cup can hold anywhere from 120 g when spooned in gently to 145 g when the cup is dipped straight into the bag. That swing is about two extra tablespoons, enough to turn a chewy cookie dry or a tender cake dense.

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 90 g of all-purpose flour?
0.75 cups, or about 3/4 cup. That is worked out at 120 g per US cup, and a cup of all-purpose flour can run 120 to 145 g depending on how the cup is filled.
How many tablespoons is 90 g of all-purpose flour?
About 12 tablespoons, since one US cup is 16 tablespoons. For small amounts tablespoons are usually the more accurate measure to work with.
Why does 90 g give a different number of cups for other ingredients?
Because cups measure volume and grams measure weight. 90 g of all-purpose flour is 0.75 cups at 120 g per cup, while the same 90 g of a denser or lighter ingredient fills a different amount of space.

Other amounts of all-purpose flour

70 g74 g75 g80 g85 g100 g110 g112 g113 g115 g

See all all-purpose flour conversions or 90 g of every other ingredient.