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20 Fluid Ounces to Cups

20 fluid ounces equals 2.5 cups using the fl oz to cup formula. Scroll down for the full calculation.

20 fl oz = 2.5 cup
fl oz ÷ 8 = cup
Try: 15 fl oz to cup 19 fl oz to cup 21 fl oz to cup 25 fl oz to cup
20 fl oz is also
20 fl oz = 0.5915 L 20 fl oz = 0.1563 gal 20 fl oz = 591.47 mL 20 fl oz = 1.25 pt 20 fl oz = 0.625 qt 20 fl oz = 40 tbsp 20 fl oz = 120 tsp
fl oz
2.5 cup

How to Convert Fluid Ounces to Cups

fl oz ÷ 8 = cup
  1. Start with 20 fl oz
  2. Divide by 8: 20 ÷ 8 = 2.5
  3. Result: 20 fl oz = 2.5 cup

The same formula works for any value. Multiply by 0.125 to go from fluid ounces to cups.

Common Fluid Ounce to Cup Conversions

Fluid Ounces (fl oz) Cups (cup)
1 fl oz 0.125 cup
2 fl oz 0.25 cup
5 fl oz 0.625 cup
10 fl oz 1.25 cup
15 fl oz 1.88 cup
20 fl oz 2.5 cup
25 fl oz 3.13 cup
50 fl oz 6.25 cup
75 fl oz 9.38 cup
100 fl oz 12.5 cup
250 fl oz 31.25 cup
500 fl oz 62.5 cup
1,000 fl oz 125 cup
calculate Fluid Ounce to Cup Converter swap_horiz Cup to Fluid Ounce Converter functions Fluid Ounce to Cup Formula water_drop All Volume / Capacity Conversions

Frequently Asked Questions

20 fluid ounces equals 2.5 cups.
The formula is: fl oz ÷ 8 = cup. See the fl oz to cup formula page for worked examples.
Use the cups to fluid ounces converter. The reverse formula is: cup × 8 = fl oz.
The calculator uses the full-precision conversion factor for accuracy. Table values and displayed results are rounded for readability.
The conversion formula (fl oz ÷ 8 = 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