Medium pasta shells

One US cup of medium pasta shells weighs between 64 and 76 grams (2.3 to 2.7 ounces), depending on how the cup is filled and which source measured it. Use 76 grams (2.7 ounces) for medium shells. Every figure behind it is below, with the method each source used.

Also called pasta shells, shell pasta, medium shells, conchiglie, macaroni shells, dry pasta shells.

Dry pasta and noodles compared: cup weights side by side, the source behind each, and why they differ.

A cup of dry medium pasta shells weighs between 64 and 76 g (2.3 to 2.7 oz). Use 76 g: the USDA Food Buying Guide counts 6 cups of medium shells to the pound and America's Test Kitchen 4 1/2 cups to 12 ounces, both 76 g a cup, and most labels agree.

Shells, conchiglie in Italian, are semolina pasta shaped like a seashell: a curled, ridged cup open at one end that scoops up sauce. They come small (for soup and macaroni and cheese), medium (the everyday size) and jumbo (conchiglioni, for stuffing).

USDA SR Legacy "Pasta, dry, enriched" (FDC 169736) lists 1 cup of shells at 64 g without naming the size. The USDA Food Buying Guide's "Shells, Medium, Enriched" gives 1 lb dry as about 6 cups, 75.6 g a cup, and America's Test Kitchen's Skillet Pasta with Peas and Prosciutto calls for "12 ounces (about 4 ½ cups) medium pasta shells", also 75.6 g; both are entered as the round 76 g. USDA's 64 g is 19% lighter, past the 10% tolerance for grains and pasta, so the page shows the range rather than set USDA aside.

Labels support 76 g. Prince prints its medium shells at "3/4 cup (56g)" and Barilla's measuring chart gives 3/4 cup per 2-ounce serving, both 75 g a cup; a retailer listing shows Skinner's medium shells at 2/3 cup (84 g). They are kept as sources without a figure, because a label's cup is rounded at a fixed 56 g serving. Large stuffing shells, which the Food Buying Guide counts at about 5 3/8 cups to the pound, and small shells, which labels such as Prince, Great Value and Kroger print at 1/2 cup per 56 g, are different sizes and not part of this figure.

The physical check: each shell is a little cup that holds air, and shells nest into each other only partly. At 76 g a cup is 0.32 g/mL. Dry semolina pasta is about 1.4 g/mL (Biernacka and colleagues, 2018, measured raw spaghetti at 1.34 to 1.45), so only about 23% of the cup is pasta, close to farfalle and well below elbow macaroni (35 to 40%). A cup that is shaken lets more shells nest inside each other, one reason the figures differ.

Cooked: the Food Buying Guide gives a pound of medium shells as 2.53 lb cooked, about 6 2/3 cups (172 g a cup), with about 17 shells to a quarter cup; USDA weighs a cup of cooked shells at 105 g (FDC 169737). A cooked cup depends on how firmly it is filled, so it is described here rather than published.

Practical guidance: use 76 g per cup of dry medium shells, 38 g per half cup; a 1 lb box holds about 6 cups. For a recipe that swaps shells for another shape, follow America's Test Kitchen's advice and go by weight, since the cup measurements will vary.