Fresh lemon juice

One US cup of fresh lemon juice weighs 244 grams (8.6 ounces). Going the other way, 100 grams is about 0.41 cups.

Citrus juices compared: cup weights side by side, the source behind each, and why they differ.

Fruit juices compared: cup weights side by side, the source behind each, and why they differ.

Fresh-squeezed lemon juice weighs 244 g per US cup — USDA (both SR Legacy and Foundation Foods records) and every aggregator source converge on this figure within 2%. Density 1.031 g/mL, slightly denser than water due to dissolved citric acid and sugars. King Arthur's 14 g per tablespoon (224 g per cup) is lighter than water and is rejected.

Fresh lemon juice is the acidic liquid squeezed from lemons (Citrus limon), typically 5-8% citric acid by weight, plus small amounts of sugars, vitamin C, and traces of pulp. USDA maintains two distinct records: "Lemon juice, raw" (SR Legacy, FDC 167747) at 244 g per US cup, and "Lemon juice, 100%, freshly squeezed" (Foundation Foods) at approximately 248 g per US cup. The 1.6% difference between the two records is within measurement variance and both are legitimately USDA-published.

USDA SR Legacy publishes 258 g per metric cup = 244 g per US cup for raw lemon juice, corresponding to density 1.031 g/mL. Bottled lemon juice from concentrate (RealLemon and equivalent brands) is USDA-documented at the same density — the water is added back to reconstitute a juice with the same solids fraction as fresh, so density does not differ measurably between fresh and reconstituted forms.

King Arthur's ingredient weight chart lists lemon juice at 1 tablespoon = 1/2 oz = 14 g. That is 224 g per cup, 0.947 g/mL, lighter than water, which lemon juice cannot be: it is water carrying dissolved citric acid and sugar, both denser than water. A tablespoon is half a fluid ounce, and 14 g is half a weight ounce, so the figure is the fluid ounce read as a weight ounce, the same mistake as King Arthur's 227 g cup of milk. It is recorded as a rejected source and has its own correction page. King Arthur also lists "Lemon Juice Powder" at 2 tbsp = 5/8 oz = 18 g, a distinct dehydrated product. Aggregator sources (CupOrGram, Cups & Grams, ezunitconverter) all cite USDA at 244 g/cup, reinforcing the reference figure.

Density is slightly above water because fresh lemon juice contains dissolved citric acid (5-8% by weight), small amounts of sugars (1-3%), and other soluble solids. Pure water at 20°C is 0.998 g/mL; lemon juice at 1.031 g/mL is about 3.3% denser, matching the expected contribution from dissolved solids in a fresh-squeezed sample. Freshly squeezed juice with significant pulp can be marginally denser (up to 1.05 g/mL) but retail-relevant strained juice sits near 1.03 g/mL.

Practical guidance: for baking (lemon curd, lemon meringue pie, lemon poundcake, lemon bars, French macarons), weigh lemon juice for consistency — a "juice of 1 lemon" varies from about 15 g (small Meyer) to 60 g (large Eureka), and typical medium-sized lemons yield 30-40 g each. A cup of fresh lemon juice requires roughly 6-8 medium lemons. For a recipe calling for 1/4 cup lemon juice, that is 61 g, or the juice of about 2 medium lemons.

The tablespoon figure (15 g) matches water's 15 g/tbsp within 3% — one useful mental shortcut is treating small quantities of lemon juice as equivalent to water by volume for most recipes. For larger quantities where the acidity affects gluten development (biscuits, quick breads with buttermilk substitutes), weigh from the reamer.

Bottled lemon juice from concentrate (RealLemon and similar) has the same density as fresh, but flavor and acidity differ slightly due to processing. Bottled products often add small amounts of preservatives (sodium benzoate, sulfites) that do not measurably shift density but do affect taste and gelling behavior in delicate applications (lemon curd, gelée, panna cotta).

Companion citrus entries: fresh-lime-juice sits at approximately 242 g/cup per USDA (marginally lighter, similar citric acid content). Vanilla-extract, another common recipe liquid, is much lighter at ~208 g/cup due to alcohol content.

The following published figures for fresh lemon juice are rejected here, with the physics or standards reasoning behind each rejection on its own page:

• King Arthur Baking Ingredient Weight Chart: 224 g per cup