Dried beans and lentils grams per cup: black beans, chickpeas, lentils and more compared

A US cup of dried beans, lentils or peas weighs between 167 and 208 grams, about 2 1/4 to 2 3/4 cups to the pound. Two things decide where each lands: how dense the seed itself is, and how much of the cup it fills, which depends mostly on its size. Cooked, lentils and split peas weigh about the same per cup as dry, and beans about 10 percent less.

All weights are for a US cup of 236.5882365 ml; a tablespoon is a sixteenth of it. A range means the sources disagree by more than this site’s tolerance for that kind of ingredient, so no single figure is chosen. King Arthur’s figure is shown where this site records one, with the verdict on it. Each ingredient’s own page has every source and the full reasoning.

Dried legumes fill a measuring cup the way any loose seed does: the seeds touch, and air fills the gaps between them. A poured cup of beans or lentils is a little over half seed and the rest air, so its weight depends on two things, how dense each seed is and how much of the cup the seeds fill.

Seed density is much the same for lentils and chickpeas: grain-handling studies measure the seed itself at about 1.4 grams per millilitre for both. Black-eyed peas are the exception. A cowpea seed measures about 1.13, so a cup of them weighs 167 grams, the lightest here, although they pack a little tighter than lentils or chickpeas.

Among the common beans, which are all one species, size decides most of the rest. A measuring cup is small next to a bean, and its walls leave gaps that the beans cannot fill, so the bigger the bean, the more of the cup is air. Navy beans, the smallest of the five, fill a cup to 208 grams; black and pinto beans weigh 193 to 194 grams; the large kidney and Great Northern beans only 183 to 184 grams. Lentils and split peas, smaller seeds but flat or split, weigh 192 to 196 grams. The same rule holds outside the common beans: small, round mung beans and baby lima beans weigh 202 to 207 grams a cup, and broad, flat large limas only 178 grams.

Chickpeas are the one entry with a range, 181 to 200 grams. USDA's cup is the heavy end. America's Test Kitchen and the USDA Food Buying Guide, which both count 2 1/2 cups to the pound, are the light end, and a poured bulk-density measurement sits between them. Use 181 grams for store-bought chickpeas.

Cooking changes the volume more than the weight per cup. Dried legumes take up water and swell to two or three times their volume: USA Pulses gives half a cup dry as one cup cooked for every pulse, and the Bean Institute one cup of dry beans as three cups cooked and drained. The water that swells each seed also fills the gaps between them, so a cup of cooked lentils or split peas weighs about the same as a cup of dry ones, 196 to 198 grams, and a cup of cooked beans about 10 percent less: 164 grams for chickpeas, 172 for black beans. Canned beans are already cooked; a 15-ounce can holds about 1 1/2 to 1 3/4 cups once drained.

For swaps, weigh. A cup of navy beans is 14 percent heavier than a cup of Great Northern beans, and a cup of chickpeas can be up to 20 percent heavier than a cup of black-eyed peas, so a recipe written by the cup shifts when the bean changes. By weight it does not.