Spice seeds in grams: celery, dill, anise, cumin, fennel, caraway, mustard and fenugreek per teaspoon compared

A US teaspoon of a whole spice seed weighs between about 2 grams for fennel and cumin and 3.7 grams for fenugreek, and a cup between about 90 and 200 grams. Shape decides most of it: the ribbed half-fruits of the parsley family stack loosely, while hard, round or angular seeds fill the spoon much more fully.

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.

Six of these seeds come from one plant family, the parsley family: celery, dill, anise, cumin, fennel and caraway. What is sold as their seed is half of a small dry fruit, ribbed or ridged along its length, and the shapes are similar enough that they weigh much the same by the spoon. USDA weighs a teaspoon of celery seed at 2.0 grams and one of dill seed or anise seed at 2.1, and its cup figures for cumin, fennel and caraway seed fall between 93 and 107 grams, 1.9 to 2.2 grams a teaspoon.

Most of these seeds are published as ranges, because the other measurements run both lighter and heavier than USDA. Bulk sellers' counts of cups to the pound make dill seed lighter, 90.7 grams a cup against 105.6, and anise seed heavier, 130 to 151 grams against 107. Caraway seed runs from 107 grams by USDA to 144 by King Arthur Baking, with three branded records between. Seed lots differ in size, plumpness and how much broken seed they carry, and none of these sources says how its cup was filled, so each page shows every figure and the span they cover.

Mustard and fenugreek are the heavy ones. Mustard seeds are small, hard spheres and fenugreek seeds small, hard, angular blocks; neither has ribs or a papery edge, so they settle into the spoon like grain. Yellow mustard seed weighs 159 to 200 grams a cup across labels and tables, and fenugreek 177.6 grams by USDA, with a foodservice table within 1.2 percent. Fenugreek is one of the few spices whose packing has been measured in a laboratory: two studies put the bulk density of the dry seed at 701 and up to 801 kilograms per cubic metre, 166 to 189 grams per US cup, and USDA's figure sits between them.

Grinding a seed changes its weight by the spoon much less than grinding a herb. In the Shamrock Foodservice spice table, ground anise weighs 12.5 percent more than whole anise seed, ground celery seed 5 percent more than whole, and ground fennel the same as whole fennel seed, while ground herbs weigh about twice their leaves. A seed is already a solid piece, and its powder fills the spoon about as well as the seeds do.

For cooking, the spoon is accurate enough: recipes use these seeds by the teaspoon, and a few tenths of a gram either way changes nothing. For pickling spice, sausage, spice blends and bread made in quantity, weigh, and never convert one seed by another's figure: a tablespoon of fenugreek weighs 11 grams, a tablespoon of dill seed 6.6. Toast whole seeds in a dry pan for a minute before grinding them to deepen their flavour.