Gram to Cup

450 grams of all-purpose flour to cups

450 g of all-purpose flour is about 3.75 cups, which is roughly 3 cups + 3/4 or 60 tablespoons. That comes from 120 g per US cup. Assumes spoon-and-level. Scooped flour runs closer to 140 g a cup.

Measure450 g of all-purpose flour
Cups3.75
Kitchen measure3 cups + 3/4
Tablespoons60
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 450 g of all-purpose flour?
3.75 cups, or about 3 cups + 3/4. 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 450 g of all-purpose flour?
About 60 tablespoons, since one US cup is 16 tablespoons. For small amounts tablespoons are usually the more accurate measure to work with.
Why does 450 g give a different number of cups for other ingredients?
Because cups measure volume and grams measure weight. 450 g of all-purpose flour is 3.75 cups at 120 g per cup, while the same 450 g of a denser or lighter ingredient fills a different amount of space.

Other amounts of all-purpose flour

300 g320 g340 g350 g375 g400 g425 g454 g500 g600 g

See all all-purpose flour conversions or 450 g of every other ingredient.