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40 Fluid Ounces to Cups

40 fluid ounces is 5 cups. See the step-by-step breakdown and reference table below, or try a different value in the calculator.

40 fl oz = 5 cup
fl oz ÷ 8 = cup
Try: 35 fl oz to cup 39 fl oz to cup 41 fl oz to cup 45 fl oz to cup
40 fl oz is also
40 fl oz = 1.18 L 40 fl oz = 0.3125 gal 40 fl oz = 1,182.94 mL 40 fl oz = 2.5 pt 40 fl oz = 1.25 qt 40 fl oz = 80 tbsp 40 fl oz = 240 tsp
fl oz
5 cup

Step-by-Step Calculation

fl oz ÷ 8 = cup
  1. Start with 40 fl oz
  2. Divide by 8: 40 ÷ 8 = 5
  3. Result: 40 fl oz = 5 cup

This conversion factor (0.125) is the same for every fluid ounce to cup calculation.

Fluid Ounce to Cup Conversion Table

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
40 fl oz 5 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

40 fluid ounces equals 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