Citrus juice grams per cup: orange, grapefruit, lemon, lime, Key lime

A US cup of fresh orange juice weighs 248 grams, grapefruit juice 247 grams, lemon juice 244 grams, bottled Key lime juice 246 grams and lime juice 242 grams. All five weigh a little more than a cup of water, about 236 grams, because of the sugars and acids dissolved in them.

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.

Dissolved solids are denser than water, so the more a juice carries, the heavier the cup. Orange juice carries the most: USDA's raw orange juice (FDC 169098) has about 10.4 grams of carbohydrate per 100 grams, almost all sugar, and weighs 1.048 grams per millilitre. Two laboratory studies that measured orange juice directly, Ramos and Ibarz in 1998 and a 2019 study, found 1.054 to 1.057 grams per millilitre, within 1% of USDA. Grapefruit juice carries a little less, 9.2 grams of carbohydrate, and weighs 1.044; US Customs laboratory methods put unconcentrated grapefruit juice at 10.2 °Brix against 11.8 for orange.

Lemon and lime juice are lighter because they are mostly acid with little sugar. Lemon juice carries 5 to 8% citric acid and 1 to 3% sugars and weighs 1.031 grams per millilitre (USDA FDC 167747). Lime juice averages slightly less acid and less sugar and weighs 1.023 (FDC 168156). Bottled Key lime juice weighs 1.040, USDA's figure for bottled lime juice (FDC 168157); a study of Mexican limes, the Key lime, measured their juice at 9 to 10 °Brix, which predicts the same weight. Every source checked agrees with USDA within 2% for orange, grapefruit, lemon and lime, and within 3% for Key lime.

Varieties and bottling barely matter. USDA's pink and white grapefruit juice records both weigh 247 grams per cup; bottled Key lime juice and fresh lime juice weigh within 2% of each other; and bottled juice reconstituted from concentrate is brought back to the same solids as fresh, so it weighs the same per cup. Retail labels are no help either way, because they state servings in millilitres, never grams.

The real variable is the fruit. USDA's survey data puts the juice of one orange at 86 grams, so a cup takes about three oranges, and one grapefruit at 196 grams, about four fifths of a cup. A cup of lemon or Persian lime juice takes 6 to 8 fruit, and Key limes 20 to 30. A tablespoon of any of the four weighs 15 to 15.5 grams, close enough to water that small amounts can be measured like water; for curds, sorbets and cocktails, weigh the juice instead of counting fruit.

King Arthur's chart lists lemon juice at 1 tablespoon = 14 grams. That is 224 grams per cup, lighter than water, which an acid juice cannot be: a tablespoon is half a fluid ounce and 14 grams is half a weight ounce, the same fluid-ounce mistake as King Arthur's 227-gram cup of milk, and this site rejects it. Its row for Key lime juice, 1 cup = 227 grams, is the same mistake and is rejected on the Key lime juice page. It has no rows for fresh orange, grapefruit or lime juice, and every figure on this page rests on USDA FoodData Central.