How do you measure 16.3 ounce peanut butter with measuring cup?

16.3 ounces / 32 ounces per quart = 0.51 quarts.

Read conversion to the nearest ½ cup:

0.51 quarts = 1 cup and 0.01 quarts.

Since 0.01 quart is just over 1/16 cup (0.0625 to be exact), round up to nearest 1/2 cup.

Measure 1 cup plus 2 tablespoons peanut butter:

1 cup = 8 fluid ounces

2 tablespoons = 1 fluid ounce

1 cup + 2 tablespoons = 9 fluid ounces