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21 Teaspoons to Cups

21 teaspoons equals 0.4375 cups. Use the formula, worked example, and conversion table below to check the math.

21 tsp = 0.4375 cup
tsp ÷ 48 = cup
Try: 16 tsp to cup 20 tsp to cup 22 tsp to cup 26 tsp to cup
21 tsp is also
21 tsp = 0.1035 L 21 tsp = 0.0273 gal 21 tsp = 103.51 mL 21 tsp = 3.5 fl oz 21 tsp = 0.2188 pt 21 tsp = 0.1094 qt 21 tsp = 7 tbsp
tsp
0.4375 cup

Step-by-Step Calculation

tsp ÷ 48 = cup
  1. Start with 21 tsp
  2. Divide by 48: 21 ÷ 48 = 0.4375
  3. Result: 21 tsp = 0.4375 cup

This conversion factor (0.020833) is the same for every teaspoon to cup calculation.

Teaspoon to Cup Conversion Table

Teaspoons (tsp) Cups (cup)
1 tsp 0.0208 cup
2 tsp 0.0417 cup
5 tsp 0.1042 cup
10 tsp 0.2083 cup
15 tsp 0.3125 cup
20 tsp 0.4167 cup
21 tsp 0.4375 cup
25 tsp 0.5208 cup
50 tsp 1.04 cup
75 tsp 1.56 cup
100 tsp 2.08 cup
250 tsp 5.21 cup
500 tsp 10.42 cup
1,000 tsp 20.83 cup
calculate Teaspoon to Cup Converter swap_horiz Cup to Teaspoon Converter functions Teaspoon to Cup Formula water_drop All Volume / Capacity Conversions

Frequently Asked Questions

21 teaspoons equals 0.4375 cups.
The formula is: tsp ÷ 48 = cup. See the tsp to cup formula page for worked examples.
Use the cups to teaspoons converter. The reverse formula is: cup × 48 = tsp.
The calculator uses the full-precision conversion factor for accuracy. Table values and displayed results are rounded for readability.
The conversion formula (tsp ÷ 48 = cup) is based on internationally defined standards. Displayed results are rounded for readability, while the calculator uses the full-precision factor.
person Written by Sean Day verified Reviewed by UnitCompare update Last updated Mar 28, 2026