White Rice Flour

One US cup of white rice flour weighs 160 grams (5.6 ounces). Going the other way, 100 grams is about 0.62 cups.

Also called rice flour, white rice flour, stone ground white rice flour, organic white rice flour, gluten-free rice flour.

TL;DR: White rice flour weighs 160 grams per cup (0.6763 g/mL) based on Bob's Red Mill's official flour weight chart, three convergent USDA Branded Foods entries for Bob's rice flour products, and USDA composition data within 1 percent. King Arthur's chart value of 142 g/cup is rejected as inconsistent with the four-way producer and USDA convergence — an unusually clean correction with no ambiguity.

White rice flour is milled from white rice — long, medium, or short grain — with the bran and germ removed, leaving the endosperm-only starch. It is the workhorse flour of gluten-free baking, Asian noodle production, and sauce thickening, produced primarily by Bob's Red Mill in the US retail market, with Arrowhead Mills, King Arthur's own gluten-free line, and a handful of smaller millers providing secondary options. This entry represents the standard spooned-and-leveled measurement for white rice flour; brown rice flour (which includes the bran and germ) is covered in a separate entry, and sweet rice flour or mochiko (from glutinous short-grain rice) is compositionally similar enough at the density level that it is often used interchangeably in bulk conversion — Bob's Red Mill lists both at exactly 160 g/cup.

Bob's Red Mill's official flour weight chart lists White Rice Flour, Organic White Rice Flour, and Sweet White Rice Flour all at 160 grams per cup. USDA Branded Foods carries independent entries for Bob's Stone Ground White Rice Flour (UPC 039978003164) and Sweet White Rice Flour (UPC 039978006080), both at 169 grams per metric cup — converting to exactly 160 grams per US cup. USDA's composition reference for white rice flour (NBD 20061) implies approximately 158 grams per cup from its calorie-per-cup ratio, within one percent of the branded and chart figures. This is convergence across a producer chart, three producer-derived USDA entries, and a USDA composition value.

King Arthur Baking's ingredient weight chart lists rice flour (white) at 142 grams per cup — 11 percent below the producer-and-USDA convergence at 160. As with the demerara correction, KA's figure fails an internal consistency check against related products: brown rice flour, which physically packs less densely than white due to larger bran-containing particles, is listed by KA at 128 g/cup, only 10 percent lighter than their white figure. But USDA and Bob's Red Mill data show brown rice flour typically at 128-152 g/cup and white at 160 — a wider gap of roughly 15-25 percent that reflects the actual physical difference between bran-laden and endosperm-only rice flours. The KA rice flour figure is best read as an anomalous chart entry.

The physical reasoning behind white rice flour's high density is worth noting. Bob's Red Mill's chart itself observes that super-fine grinds pack more per cup, explicitly using Sweet White Rice Flour as their example. This is opposite to wheat flour, where cake flour (fine) is lighter than AP flour. Rice starch granules are denser and more spherical than wheat starch granules, so they nestle into a spooned cup with fewer air gaps. Rice flour at 160 g/cup is among the heaviest common flours by volume, exceeded only by starches (cornstarch at 128, potato starch at 152) and certain bran-heavy products (whole cornmeal at 138). Wheat AP flour at 120 g/cup is a full 25 percent lighter per cup than white rice flour, which matters in any recipe substituting one for the other by volume.

Practical baker recommendation: use 160 g/cup for white rice flour. Weigh rather than measure by cup — the density is high enough that even small volume errors translate to meaningful mass differences. If a recipe was developed against KA's 142 g/cup and you weigh out 160 g for a cup call, you will be adding 13 percent more flour than the recipe expected. In gluten-free applications where rice flour provides most of the structure, that difference matters.

The following published figures for white rice flour are rejected here, with the physics or standards reasoning behind each rejection on its own page:

• King Arthur Baking (Ingredient Weight Chart): 142 g per cup