Cooking Conversion Guide

Cooking conversion is the everyday task of moving recipe measurements between cups, tablespoons, teaspoons, fluid ounces, millilitres, grams, and ounces. Two patterns matter. First, volume to volume — cups to millilitres, tablespoons to teaspoons — which is straightforward as long as you keep track of which 'cup' you are using. Second, volume to weight — cups to grams, tablespoons to grams — which is straightforward for water but ingredient-dependent for anything else, because flour, sugar, butter, and honey all have different densities.

Our cooking category routes volume through the US cup (236.5882365 mL) by default and uses water density (1 g/mL) for the volume-to-weight bridge. Ingredient-specific conversions use a published density table covering 60+ common ingredients with grams per cup, tablespoon, and teaspoon. That data sources from USDA FoodData Central and standard culinary references, so 'a cup of all-purpose flour' returns 120 g (spooned and levelled) rather than the literal 236.6 g a water-based bridge would give.

Cooking is the only Calcflux category where unit conversion needs a third input — the ingredient — to produce a useful answer. If you ask 'how many grams in a cup', the honest answer is 'depends what you are measuring'. For water it is 236.6 g; for granulated sugar it is roughly 200 g; for all-purpose flour it is about 120 g.

Volume-based cooking measurement is American. European cooking traditionally used weight — a kitchen scale, with everything in grams — because precision flour-baking required it. American 20th-century home cooking moved to cups, tablespoons, and teaspoons because they were faster and required no scale, with the trade-off being repeatability. Fannie Farmer's 1896 cookbook is usually credited with standardising US level-cup measurement.

The US customary cup was defined as 1/16 of a US gallon = 236.5882365 mL. The US legal cup, used on FDA nutrition labels (21 CFR 101.9, effective 1994 under the Nutrition Labeling and Education Act), is 240 mL exactly — a rounded value chosen so that 8 labeling-fluid-ounces of 30 mL each match exactly. The metric cup, used in Canada, Australia, New Zealand, and modern UK cookbooks, is 250 mL exactly. The Commonwealth metric tablespoon is 15 mL (modern UK and NZ standard, also the FDA labeling tablespoon), while Australia uses 20 mL. The US tablespoon is 14.7868 mL — derived from 1/2 US fl oz = 1/256 US gallon.

The professional baking world resolved this mess by going back to grams. Every serious modern baking book publishes ingredient weights, not cup volumes, because flour density depends on humidity, packing, and brand. King Arthur Baking, USDA FoodData Central, and culinary schools converge on a working set of densities — all-purpose flour at about 120 g/cup spooned, granulated sugar at about 200 g/cup, butter at 227 g/cup (two sticks). Our ingredient-density data uses these working values rather than letting users discover them by trial and error.

Our cooking category supports nine units across two families. Volume (base: US customary cup): cup, tablespoon, teaspoon, fluid ounce, millilitre. Weight (bridged to cups via density): gram, ounce, pound, kilogram. The volume units use US customary values: 1 cup = 236.5882365 mL, 1 tablespoon = 1/16 cup, 1 teaspoon = 1/48 cup, 1 fluid ounce = 1/8 cup. The weight-to-volume bridge uses water density (1 g/mL) by default and accepts an ingredient name to apply the published per-ingredient density.

We do not include separate UK or metric cups directly in the cooking category because they would compound the existing confusion. If you have a UK recipe in metric cups, the most reliable approach is to convert the volume to millilitres first and run the cooking conversion from millilitres — bypassing the cup ambiguity entirely. Our volume category handles UK pints, imperial fluid ounces, and the metric cup explicitly.

Every cooking conversion routes through the US cup as the base. Volume units are exact multiples — 1 tablespoon = 1/16 cup, 1 teaspoon = 1/48 cup, 1 fluid ounce = 1/8 cup, 1 millilitre = 1/236.5882365 cup. Weight units use water density as the default bridge: 1 gram of water = 1/236.5882365 cup. For non-water ingredients, the converter UI layer looks up the ingredient in the density database before calling the base conversion function. The cooking section of our methodology page lists every factor and notes the ingredient-density bridge.

Useful approximations for water-equivalent quantities: 1 US cup ≈ 236.6 mL = 236.6 g. 1 US tablespoon ≈ 14.79 mL = 14.79 g. 1 US teaspoon ≈ 4.93 mL = 4.93 g. For ingredient-specific anchors using our published densities: 1 cup all-purpose flour (spooned) ≈ 120 g. 1 cup granulated sugar ≈ 200 g. 1 cup butter ≈ 227 g. 1 cup honey ≈ 340 g.

Recipe translation drives most cooking searches. Cups to tablespoons handles scaling within American recipes — 1 cup = 16 tablespoons exactly. Tablespoons to teaspoons is the most common small-quantity conversion — 1 tablespoon = 3 teaspoons. Grams to cups is the heaviest-traffic cross-system conversion: a European baking recipe specifies 240 g of bread flour, which with our flour density works out to roughly 2 cups. Cups to milliliters translates US recipes into metric for kitchens without a US measuring cup.

The full cooking comparison table lists every supported unit with its cup factor and a worked sample. Use it when you are converting an entire recipe at once rather than one ingredient at a time. For ingredient-aware conversions, the cooking converter accepts an ingredient picker that switches the density bridge accordingly.

Cup is not equal to cup: US customary cup = 236.6 mL; US legal cup = 240 mL; metric cup = 250 mL; UK cup = 284.1 mL. The 17% gap between US customary and UK cups translates directly to ingredient weights — a UK recipe asking for 'a cup of butter' wants 273 g, not the 227 g a US 'cup of butter' delivers. Always check the recipe's origin.

Tablespoon is not equal to tablespoon: US tablespoon = 14.79 mL; modern UK/NZ tablespoon = 15 mL; Australian tablespoon = 20 mL. The historical imperial UK tablespoon was 17.76 mL (½ imperial fluid ounce) and still appears in older British cookbooks. The Australian tablespoon is 35% larger than the US one, which makes recipe scaling between the two regions noticeably wrong if you use a single 'tbsp' label.

Flour weight depends on technique: USDA FoodData Central lists all-purpose flour at 125 g/cup. King Arthur Baking lists 120 g/cup spooned and levelled. Scoop-and-shake technique packs flour to 144–160 g/cup, which is why most baking books explicitly say 'spoon flour into the cup and level off' — the technique can change the weight by 20% on the same flour. If you can use a scale, use the scale.

Butter stick measures: US butter ships in 113-gram sticks marked in tablespoon-equivalents on the wrapper. UK butter ships in 250-gram blocks and is portioned by weight only. American 'half a stick' is 56.7 g; UK recipes never say 'half a stick' because UK butter is not packaged that way. Our ingredient density for butter (227 g/cup, equivalent to 14.2 g/tablespoon) reflects the US convention.

Liquid versus dry measure cups: in the US, 'liquid measure' cups have a pour spout and a small headspace; 'dry measure' cups are level-filled. Both hold the same 236.6 mL when measuring water, but the convention is that dry ingredients are levelled with the rim of the cup and liquid ingredients are read at the meniscus from the side. Pour-spout cups have no rim to level against, which is why serious bakers use weight.

Side-by-side: the full cooking comparison table lists every supported unit with its factor and a worked sample. Definitions: glossary entries for US cup, US tablespoon, millilitre, and gram. Method and sources: the cooking section of our methodology page cites USDA FoodData Central and culinary-school working densities. Context: our piece on why bakers weigh instead of measuring volume covers the cup-of-flour problem in detail.