Odd fractions as cups and spoons
Measuring cup sets usually hold 1, 1/2, 1/3 and 1/4 cup. Scale a recipe and you'll soon meet 1/6 cup or 5/8 cup, which none of them hold. The fix is to make up the amount from cups and spoons.
The three numbers you need (US measures)
- 1 cup = 16 tablespoons
- 1 tablespoon = 3 teaspoons
- So 1 cup = 48 teaspoons
To convert any fraction of a cup, multiply by 16 to get tablespoons. Whatever is left over, multiply by 3 for teaspoons. For 1/6 cup: 16 ÷ 6 = 2⅔ tablespoons, which is 2 tablespoons and ⅔ × 3 = 2 teaspoons.
Common awkward fractions (US cups)
| Fraction | Measure as |
|---|---|
| 1/16 cup | 1 Tbsp |
| 1/12 cup | 1 Tbsp + 1 tsp |
| 1/8 cup | 2 Tbsp |
| 1/6 cup | 2 Tbsp + 2 tsp |
| 3/8 cup | 1/4 cup + 2 Tbsp |
| 5/8 cup | 1/2 cup + 2 Tbsp |
| 5/6 cup | 3/4 cup + 1 Tbsp + 1 tsp |
| 7/8 cup | 3/4 cup + 2 Tbsp |
All of these are exact in US measures.
When we show "≈"
Some amounts don't break down neatly. 0.3 cup (US) is 4.8 tablespoons, or 4 tablespoons and 2.4 teaspoons. The recipe scaler rounds the teaspoon part to the nearest 1/8 teaspoon and marks the result "≈" so you know it isn't exact. It also never shows a fraction like "1/3 cup" for a value that is only close to 1/3 without the "≈".
Metric and Australian measures
A metric cup is 250 mL and a metric tablespoon is 15 mL, so a metric cup is 16⅔ tablespoons, not 16. An Australian tablespoon is 20 mL, which makes a cup 12½ tablespoons. The table above only works with US measures. In the scaler, choose the measures you own and the breakdown uses those sizes.
When the fractions get really awkward, weighing is easier. The cups to grams converter gives an estimated weight for common baking ingredients.
Sources
- NIST Handbook 44 (2026), Appendix C. 1 cup = 8 fl oz = 16 tablespoons; 1 tablespoon = 3 teaspoons
- Edmonds, Weights & measures. Metric 250 mL cup, 15 mL tablespoon; Australian 20 mL tablespoon