Pistachios

One US cup of pistachios weighs 123 grams. Going the other way, 100 grams is about 0.81 cups.

Also called shelled pistachios, pistachio nuts, pistachio kernels, raw pistachios.

Two sources agree within tolerance. USDA FDC 170184 (Nuts, pistachio nuts, raw, SR Legacy) publishes 1 cup at 123 g, implying a density of 0.5199 g/mL. King Arthur's Ingredient Weight Chart lists 'Pistachio nuts (shelled)' at 1/2 cup = 60 g (120 g per cup), implying 0.5072 g/mL. The gap between them is 2.44%, well inside the 10% milled tolerance for whole and chopped nuts, so this entry publishes USDA's figure of 123 g per cup and names both sources. Neither source names a specific filling method.

Pistachio kernels sit at the upper end of the tree-nut density band that this site tracks. For comparison, pecan halves publish here at 99 g per cup (density 0.4185 g/mL) and walnut halves publish as a range of 99 to 128 g per cup because their sources disagree. Pistachios are physically smaller than either, at approximately 49 kernels per ounce or roughly 0.57 g per kernel, and the smaller unit size allows them to nestle more efficiently in the cup, leaving fewer air gaps than the larger nuts. This is why the apparent density is higher despite the kernels themselves not being significantly denser than pecan or walnut meat. The same size-driven packing effect explains why almonds also publish denser than pecan halves on this site.

Pistachio paste is a separate product and does not belong to this entry. King Arthur lists Pistachio Paste at 78 g per 1/4 cup (312 g per cup), which reflects a smooth, homogeneous confectionery ingredient more similar to almond butter or tahini in category than to whole kernels. The paste will be added as its own entry when a second authoritative source becomes available. Similarly, chopped or ground pistachios pack noticeably denser than whole kernels because the pieces break the air-gap geometry of the intact crescent shape, and would warrant a separate entry with its own sourcing.

Additional variant notes: dry-roasted pistachios show a moisture drop of approximately 4% relative to raw, which slightly increases apparent density but rarely enough to cross tolerance. Salted versus unsalted differs by 1 to 2% by weight from added sodium, well inside measurement noise. In-shell pistachios roughly double the total weight because the shell-to-kernel mass ratio approaches 1:1, so cup measurements of in-shell nuts are not useful for baking and this entry does not attempt to publish one.

Pistachios are placed in the milled category alongside other whole and chopped nuts, whole seeds, and whole grains. The category rule assigns these to milled because they pack by scoop with air gaps rather than filling by fluid displacement. The 10% category tolerance applies here, and the 2.44% observed gap between sources is comfortably inside it.

No standards body publishes a bulk density for pistachios or other tree nuts. Codex Alimentarius standards for tree nuts cover moisture content, defect tolerances, shell fragment limits and aflatoxin limits but not physical density. Two independent authoritative sources agree within tolerance, so this entry is held at medium confidence. A third independent source, such as a professional culinary reference or a producer's laboratory measurement, matching within tolerance would move it to high confidence.