Cooking Measurement Converter — Cups, Ounces and Grams
This cooking measurement converter turns cups, ounces, pounds, tablespoons and teaspoons into grams and milliliters, showing every factor applied and the reference density behind each cups to grams conversion.
0 to 1,000,000
Distinct conventions, never mixed
Reference density used for volume ↔ mass conversions
Calculated results
A cup convention is required: the US cup (236.588 ml) and the metric cup (250 ml) are distinct units.
Historical measures varied by country and era: without a specific variant, a historical conversion is considered undetermined.
Standard US volumes (cup 236.588 ml, tablespoon 14.787 ml, teaspoon 4.929 ml).
Method and limits
How to use this calculator
Enter the value to convert, pick the source unit — pound, ounce, cup or spoon — and the target unit. For cups and spoons, specify the convention: US customary or metric. For any conversion between volume and mass, select the ingredient: its reference density drives the result. Finally, pick the display precision, from zero to four decimal places.
Mass and volume units convert through documented fixed factors (NIST): 1 lb = 453.59237 g, 1 oz = 28.349523125 g, 1 US cup = 236.5882365 ml. Volume becomes mass through m = ρ × V, where ρ is the ingredient's reference density in g/ml; conversely, V = m / ρ. That step stays approximate for ingredients whose settling and particle size vary.
Exact factors: masses and volumes
Mass conversions rest on exact legal definitions: 1 lb = 453.59237 g and 1 oz = 28.349523125 g (avoirdupois) — the pounds to grams and ounces to grams numbers every US recipe leans on. Customary US volumes follow NIST tables, tablespoons to milliliters included: cup 236.5882365 ml, tablespoon 14.7867648 ml, teaspoon 4.92892159 ml — exactly 16 tablespoons per cup and 3 teaspoons per tablespoon. Metric conventions — cup 250 ml, spoons 15 and 5 ml — are handled separately, never mixed: the tool always shows the factors it applies.
Densities: when volume becomes mass
Converting volume to mass applies m = ρ × V; conversely, V = m / ρ. The versioned table covers water (1 g/ml), all-purpose flour (0.52 g/ml, ± 0.08 depending on settling), granulated sugar (0.85), butter (0.96) and vegetable oil (0.92) — never water's density for another ingredient. A US cup of water thus weighs 236.59 g, a cup of flour 123.03 g under the displayed convention. Density depends on settling, humidity and particle size: the uncertainty is shown with the result.
Worked example
One US cup of water converted to milliliters shows 236.59 ml — the value loaded by default. One pound is 453.59 g, one ounce 28.35 g, and a US tablespoon of water measures 14.79 ml. A US cup of all-purpose flour weighs 123.03 g at the reference density of 0.52 g/ml; a cup of granulated sugar, 201.10 g at 0.85 g/ml. Reproduce these values in the tool: you must get exactly the same results.
Assumptions and limits
US mass and volume factors are exact definitions; densities are versioned conventions, shown with their uncertainty — never universal standards. The US cup (236.588 ml) and the metric cup (250 ml) are distinct units: mixing them up skews a recipe by about 6%. Historical measures varied by country and era: without a specific variant, a historical conversion is considered undetermined. For precision baking, a gram scale remains the reference tool.
| Constant | Value | Source |
|---|---|---|
| Avoirdupois pound to gram (exact) | 453.59237 g | NIST — Guide for the Use of the International System of Units (SP 811) |
| Avoirdupois ounce to gram (exact) | 28.349523125 g | NIST — Guide for the Use of the International System of Units (SP 811) |
| US customary cup to milliliter (exact) | 236.5882365 ml | NIST — Guide for the Use of the International System of Units (SP 811) |
| All-purpose flour, lightly settled | 0.52 g/ml | Tables de densité culinaires usuellesUncertainty : ±0.08 g/ml depending on settling and particle size. |
Frequently asked questions
Limits of use