Core answer: 1 US cup = 236.6 mL ≈ 16 tbsp; 1 tbsp = 3 tsp = 15 mL; 1 tsp = 5 mL. But cups measure VOLUME and recipes often need MASS: 1 cup of flour ≈ 125 g, sugar ≈ 200 g, butter ≈ 227 g, rice ≈ 185 g. Chinese home measures: 1 汤匙 ≈ 15 mL, 1 茶匙 ≈ 5 mL, "适量" is unfortunately not a unit.
Volume measures
| Measure | mL | Notes |
|---|---|---|
| 1 tsp / 茶匙 | 5 | baking powder, salt |
| 1 tbsp / 汤匙 | 15 | oil, soy sauce |
| 1 US cup | 236.6 | US recipes |
| 1 metric cup | 250 | AU/UK modern |
| 1 fl oz | 29.6 | US liquids |
The volume-to-weight bridge (where recipes fail)
| Ingredient (1 US cup) | Grams |
|---|---|
| All-purpose flour (spooned) | ~125 |
| Bread flour | ~130 |
| Granulated sugar | ~200 |
| Brown sugar (packed) | ~220 |
| Powdered sugar | ~120 |
| Butter | 227 (1 US stick = 113 g) |
| Rice (uncooked) | ~185 |
| Water / milk | 236–245 |
| Honey | ~340 |
Flour is the trap: scooping compacts it to 150+ g/cup vs 125 g spooned — a 20% swing that turns cakes into bricks. Weigh flour, always.
Worked examples
Example 1 — Converting a US cookie recipe. "2¼ cups flour, 1 cup butter, ¾ cup sugar" → 280 g flour, 227 g butter, 150 g sugar. Note 225/227/2.25 — the decimals matter.
Example 2 — Doubling for a crowd. A soup calling for 2 tbsp salt (30 mL ≈ 36 g) doubled blindly for 20 people oversalts; scale salt/spices to ~1.5× first, taste, adjust.
Example 3 — Chinese recipe translation. "生抽2汤匙、老抽1茶匙、糖少许" → 30 mL light soy, 5 mL dark soy, "a pinch" ≈ 2–3 g sugar.
Example 4 — Rice cooker math. The included 180 mL rice cup ≈ 150 g dry rice → ~330 g cooked; plan 1 cup per adult.
Common mistakes and myths
- Treating 1 cup = 250 g for everything — only water-like liquids sit near 1 g/mL; flour is half that, honey is 1.4×.
- US vs metric cups — 236.6 vs 250 mL is a 5% gap; negligible for soup, meaningful for macarons.
- Heaping vs level — a heaping tbsp of baking powder (12 g) vs level (6 g) doubles leavening; recipes mean level unless stated.
- Ignoring temperature in butter — "1 cup butter" melted vs solid differs in aeration; weigh it (227 g) to be safe.
- Oven-proofing conversions blindly — when scaling recipes >2×, leavening and salt scale sub-linearly; bake times don't scale at all.