Vanilla wafer crumbs

One US cup of vanilla wafer crumbs weighs 80 grams (2.8 ounces). Going the other way, 100 grams is about 1.25 cups.

Crumbs and cereals compared: cup weights side by side, the source behind each, and why they differ.

A cup of vanilla wafer crumbs weighs about 80 g (2.8 oz), and a tablespoon about 5 g. USDA weighs a cup of vanilla wafer crumbs at 80 g, and King Arthur Baking's chart puts a cup of cookie crumbs at 85 g, 6% apart.

Vanilla wafer crumbs are crushed vanilla wafers, the small, light, round cookies sold in the US as Nilla Wafers and as store brands. They make the crust for banana cream and key lime pies, cheesecakes and icebox desserts, and they are the crumb in rum balls and some banana puddings. Most cooks crush them at home, in a food processor or in a bag with a rolling pin.

USDA's record for lower-fat vanilla wafers weighs a cup of crumbs at 80 g; its record for the regular, higher-fat wafers has no cup portion. King Arthur Baking's chart lists cookie crumbs at 3 oz, 85 g, a cup without naming the cookie. The two are 6.3% apart, inside the 10% this site allows for crumbs and other milled ingredients, so this site publishes USDA's 80 g. Confidence is medium: there are two sources, one of them for a lower-fat wafer and the other for crumbs of an unnamed cookie.

Nilla's label gives a serving as 8 wafers, 30 g, which is useful for counting but is not a volume.

The physical check: vanilla wafers are among the lightest crisp cookies, puffed and airy inside, and they crush into soft, irregular crumbs that hold a lot of air between them. A cup of their crumbs should weigh less than graham cracker crumbs, which come from a denser, flatter cracker and weigh about 102 g a cup on this site, and much less than chocolate wafer crumbs, which USDA weighs at 112 g. King Arthur's slightly heavier figure fits crumbs crushed a little finer or pressed down a little when the cup was filled.

Practical guidance: use 80 g per cup of vanilla wafer crumbs and about 5 g per tablespoon. At about 3.75 g a wafer, a cup of crumbs takes about 21 wafers, and an 11 oz box (311 g) makes nearly 4 cups. A 9-inch crust usually takes about 1 1/2 cups, 120 g, of crumbs with 4 to 5 tablespoons of melted butter. Crush the wafers finely for a firm crust; coarse crumbs leave gaps that crack when the crust is cut. Pulse them in a food processor or crush them in a sealed bag with a rolling pin, and measure the crumbs loosely, without pressing them into the cup.