A “cup” in a recipe is not a universal unit. Metric, United States customary, and United Kingdom imperial kitchen measures all differ — enough to throw off cakes, sauces, and bread. Converting through millilitres keeps everything consistent, which is what our Cups and Spoons converter does behind the scenes.
Metric (Australia, New Zealand, much of Europe)
- Teaspoon: 5 mL
- Dessert spoon: 10 mL
- Tablespoon: 15 mL
- Cup: 250 mL
United States customary
- Teaspoon and tablespoon: derived from the US fluid ounce (29.5735 mL)
- Cup: 236.588 mL (8 US fluid ounces)
US recipes on the web almost always mean this cup, not the 250 mL metric cup.
United Kingdom imperial
- Teaspoon, dessert spoon, tablespoon: derived from the UK fluid ounce (28.4131 mL)
- Cup: 284.131 mL (½ imperial pint)
Older British recipes may use these; modern UK cookbooks often print metric ml instead.
Worked example
2 US cups of milk ≈ 2 × 236.6 ≈ 473 mL. The same recipe written for metric cooks might say 500 mL (2 metric cups) — about 6% more liquid. For flour the gap matters too because volume measures pack differently; weighing in grams is more reliable for baking.
Practical tips
- Check where the recipe was published before assuming cup size.
- Measure your own spoons and cups in millilitres once — labels are not always accurate.
- For liquids, convert to mL; for dry ingredients, prefer weight where the recipe allows.
FAQs
- Is an Australian cup the same as metric?
- Yes — 250 mL is standard in Australian and New Zealand home cooking.
- Why do my US and UK tablespoons differ?
- They are tied to different fluid-ounce definitions; the UK tablespoon is slightly larger.
- What about Japanese cups?
- Japanese rice cups (合) are about 180 mL — not covered by our converter; use millilitres directly.
Sources
NIST Guide for SI Units; UK Weights and Measures Act definitions for imperial kitchen units.