Farro

One US cup of farro weighs between 180 and 208 grams, depending on how the cup is filled and which source measured it. That range is the answer; a single number would not be. Every figure behind it is below, with the method each source used.

Also called farro, farro perlato, pearled farro, farro integrale, whole grain farro, farro semiperlato, semi-pearled farro, emmer wheat, emmer farro.

Farro publishes as a range 180 to 208 grams per cup because commercial farro products vary meaningfully in cup weight based on pearling level, and no King Arthur reference figure exists to anchor a single value. The range represents the honest span between pearled farro (hull removed, faster cooking, most common in US retail) at the lighter end and whole-grain farro (hull retained, longest cooking, most nutrient-dense) at the denser end.

Bob's Red Mill sells two distinct farro products with cleanly separated cup weights: Organic Pearled Farro at 45 grams per 1/4 cup (180 g/cup, density 0.7609 g/mL) and Organic Whole Grain Farro at 52 grams per 1/4 cup (208 g/cup, density 0.8792 g/mL). The 15% gap between these two products from the same producer is not a labeling artifact — both use non-RACC gram values reflecting actual product measurement. In Harvest Organic Farro and Kroger Farro (both pearled) label 45 g per 1/4 cup identically, matching Bob's pearled figure precisely. This multi-producer cross-validation at 180 g/cup gives strong confidence in the pearled end of the range. USDA FoodData Central includes Branded Foods entry 45015716 (WHOLE GRAIN EMMER FARRO) as a nutritional reference but does not consistently publish cup portions across its farro entries.

Understanding farro requires knowing that the term is not species-specific in the US market. In Italy, farro properly refers to any of three ancient wheat species: farro piccolo (einkorn, Triticum monococcum), farro medio (emmer, Triticum dicoccum), and farro grande (spelt, Triticum spelta). Emmer wheat is the most common commercial farro in both Italy and the US export market. All three species are ancient relatives of modern bread wheat, cultivated for 7,000 to 12,000 years, and all retain more of the original grain nutrition than modern refined wheat. Farro is not gluten-free but is lower in gluten than modern bread wheat and is often better tolerated by people with mild wheat sensitivity, though not by those with celiac disease.

Physical mechanism for the density spread: whole-grain farro (farro integrale) retains the outer hull and bran layer intact, adding mass to each grain while barely increasing volume — this is why 1 cup of whole-grain farro weighs more (208 g) than 1 cup of pearled farro (180 g). Pearled farro (farro perlato) has the hull and outer bran removed via abrasion, leaving only the endosperm and germ. The pearled grains occupy roughly the same cup volume as whole-grain (kernels of similar size) but weigh less because material has been physically removed. Semi-pearled farro (farro semiperlato) sits between the two, typically 190-195 g/cup, retaining part of the bran for nutritional value while still cooking in reasonable time.

Compared to other whole grains and grain-like ingredients on the site, farro at 180-208 g/cup packs similar to other intact cereal grains: amaranth grain at 193 g/cup, quinoa in a comparable range, and wheat berries close to 200 g/cup. The intact-grain category consistently packs denser than the milled-flour category because unbroken kernels have less air trapped between and within particles. All-purpose flour at 120 g/cup weighs much less per cup than any whole grain despite being the same underlying wheat, because milling incorporates air voids that intact grains lack.

Category assignment is milled, matching other whole grains on the site under the fibrous-plant-particulate definition.

Confidence is low reflecting the 15% gap between pearled and whole-grain farro and the absence of a King Arthur reference. For cooking accuracy, weigh farro rather than measuring by volume. If a recipe was developed against pearled farro (most common in US retail), use 180 g/cup. If developed against whole-grain farro, use 208 g/cup. If in doubt about the pearling level, use 190 g/cup as a middle estimate matching semi-pearled products. This entry represents a moat play for the site: no other cup-to-gram reference explicitly distinguishes pearled from whole-grain farro with the physical mechanism explanation, and no other reference makes the multi-producer cross-validation (Bob's Red Mill, In Harvest, Kroger) transparent for an ancient grain that King Arthur has not indexed.