ConvBolt — Unit ConverterFluid ounces to US cups Converter
Converting fluid ounces to US cups is a multiplication by a fixed factor: 1 fl oz = 0.125 cup. The table below covers the values people look up most often, and the formula section shows exactly where that factor comes from.
Because one fluid ounce works out to 0.125 cup, the us cup is the much smaller unit of the two: a figure given in us cup always carries a smaller number than the same measurement in fluid ounce. A chart drawn in fl oz can hide that, so check which label the axis uses before you compare two readings.
When a container size is certified in US cups but you are dosing in fluid ounces, it pays to convert from the certified figure rather than from a rounded label.
The conversion factor used here is 0.125 cup per fluid ounce (3 significant digits as shown). Kept to seven figures it covers professional measurement; if you round it to two or three decimals for a spreadsheet, the error scales with the input — at a value of 1,000 fl oz a factor rounded to three decimals can be off by a measurable amount. The reverse direction uses 8 fl oz per cup, the exact reciprocal, so a round trip through both pages returns your original number.
Fluid ounces to US cups formula
Use this formula to convert any fluid ounce value to US cups:
Worked example: 100 fl oz × 0.125 = 12.5 cup.
Fluid ounces to US cups conversion table
| Fluid ounces (fl oz) | US cups (cup) |
|---|---|
| 0.5 fl oz | 0.0625 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 |
| 20 fl oz | 2.5 cup |
| 50 fl oz | 6.25 cup |
| 100 fl oz | 12.5 cup |
| 500 fl oz | 62.5 cup |
| 1000 fl oz | 125 cup |
How to convert fluid ounces to US cups
Multiply the fluid ounce value by 0.125 to get the equivalent in US cups. This single factor works for every value in the table above and for anything else you need — there is no per-value adjustment, which is why a conversion table and a calculator always agree.
If you need the opposite direction, use the US cups to Fluid ounces converter instead of dividing by hand; both pages use the same source factors. For every other fl oz conversion in one place, see the fl oz conversion hub.
Frequently asked questions
How many US cups are in 1 fluid ounce?
1 fluid ounce = 0.125 cup.
What is 100 fluid ounces in US cups?
100 fl oz = 12.5 cup.
Is converting fluid ounces to US cups the same as US cups to fluid ounces?
No — the direction changes the multiplier. The reverse conversion (1 cup = 8 fl oz) is on the US cups to Fluid ounces page.
Related conversions
Try the ConvBolt Unit Converter for any other volume unit, browse the Volume conversions, or read our conversion guides.