Cooking measurement conversion
A US cup ≈ 240 mL is the usual cooking assumption; Australian (250 mL) and Japanese (200 mL) cups differ.
| Measure | US | Metric approx |
|---|---|---|
| 1 teaspoon (tsp) | 1 tsp | 5 mL |
| 1 tablespoon (tbsp) | 3 tsp | 15 mL |
| 1 cup | 16 tbsp | 240 mL |
| 1 stick butter (US) | 1/2 cup | 113 g |
| 1 cup flour (approx) | — | 120–125 g |
| 1 cup sugar (granulated) | — | 200 g |
| Oven gas mark 4 | ≈350 °F | ≈180 °C |
| Oven gas mark 6 | ≈400 °F | ≈200 °C |
| Water boil | 212 °F | 100 °C |
Notes
- Weight of a “cup of flour” varies with packing — prefer a scale for baking.
- Butter stick size differs outside the US.
Why US and metric recipe units differ
American recipes are built on volume — teaspoons, tablespoons, and cups — while most of the world weighs ingredients. The chain is consistent: 1 tablespoon (tbsp) equals 3 teaspoons (tsp) and about 15 mL, and 1 cup equals 16 tablespoons, taken as 240 mL in US cooking. The catch is that a "cup" is not a global constant: the Australian recipe cup holds 250 mL and the Japanese cup 200 mL, so a foreign recipe measured in cups can be off by up to 20 percent. Professional bakers avoid the problem entirely by weighing in grams, which is why most serious conversions end at a kitchen scale rather than a set of measuring cups.
Converting a recipe without breaking it
Work through the spoon chain first, because it is exact: multiply tablespoons by 3 to get teaspoons, and remember that 1 tsp is about 5 mL while 1 tbsp is 15 mL. For larger amounts, convert cups to milliliters at 240 mL per US cup, then compare against the country of origin — add volume if the recipe is Australian, subtract if it is Japanese. Oven temperatures are a separate step: gas mark 4 corresponds to roughly 350 °F or 180 °C, the classic moderate setting for cakes and cookies, while gas mark 6 is about 400 °F or 200 °C. Boiling water at 212 °F / 100 °C is a useful sanity check for any thermometer.
Cups of flour and sugar: why weight wins
A cup measures space, not substance, so its weight depends on the ingredient and how you fill it. Granulated sugar is fairly forgiving at about 200 g per US cup, since the crystals settle consistently. Flour is the opposite: the same cup can weigh anywhere from about 120 to 125 g depending on whether it was spooned in lightly or scooped and packed, and a scooped cup can carry far more. That 5–10 percent spread is enough to turn bread dough rubbery or cookies dry. Weighing flour — and ideally everything else — is the single cheapest upgrade for reproducible baking, especially when translating between US and metric recipes.
Butter, sticks, and getting oven heat right
Butter is where US and metric kitchens collide hardest. A US stick is half a cup and weighs about 113 g, so four sticks make the 1-pound (454 g) block American wrappers advertise; elsewhere butter is sold in 200 g or 250 g blocks with gram markings on the wrapper, so convert by weight, not by cups. When a recipe gives an oven setting in gas marks, gas mark 4 (~350 °F / 180 °C) suits cakes and cookies, while gas mark 6 (~400 °F / 200 °C) suits bread and roasting. Finally, trust an oven thermometer: boiling water at 212 °F (100 °C) tells you in one minute whether your dial is honest.
Frequently asked questions
- How many teaspoons are in a tablespoon?
- One US tablespoon equals 3 teaspoons, or about 15 mL.
- How many mL are in a cup?
- A US cup is usually taken as 240 mL in cooking; the Australian cup is 250 mL and the Japanese cup is 200 mL.
- What is 350 °F in Celsius for baking?
- 350 °F is about 180 °C (gas mark 4), the classic moderate oven temperature for cakes and cookies.
One US tablespoon equals 3 teaspoons and about 15 mL; one US cup equals 240 mL.