How Many Ounces Does a Red Solo Cup Hold?
18 fl oz
The red Solo party cup holds 18 fluid ounces, about 532 ml, according to its maker, Solo.
In kitchen measures that is 2.25 cups, or 1.125 US pints.
Red Solo cup size and the original lines
| Measure | US fl oz | Milliliters | US cups |
|---|---|---|---|
| Red party cup (listed size) | 18 | 532 | 2.25 |
| Top line on the original cup (roughly) | 12 | 355 | 1.5 |
| Middle line on the original cup (roughly) | 5 | 148 | 0.625 |
| Bottom line on the original cup (roughly) | 1 | 30 | 0.125 |
| Smaller clear plastic cup | 10 | 296 | 1.25 |
What do the lines on a Solo cup mean?
The lines were on the original red cup, which Solo launched in the 1970s. According to Solo's FAQ, they roughly equaled 1 fl oz, 5 fl oz and 12 fl oz.
Solo gives the lines no official purpose. It says they mean something different for everyone: a measured pour for some people, a firmer grip for others, and cups that stack without sticking for kids.
Today's red party cup has no lines at all, so they only help if you still have older cups. Even then, Solo describes them only as rough amounts, so use a measuring cup when an exact amount matters.
Does a Solo cup hold a pint?
It holds a little more than a US pint and a little less than a UK pint. A US pint is 16 fl oz, so the red cup holds 1.125 US pints.
A UK (imperial) pint is 568 ml, while the red cup holds about 532 ml, or 0.94 of a UK pint. These comparisons use the listed size of the cup, not a comfortable pour.
What other sizes does Solo make?
Solo's own product catalog lists a clear plastic cup the same size as the red one and a smaller clear cup of 10 fl oz. The smaller cup holds 1.25 cups, a little more than one measuring cup.
If your cups came in another size, go by the package. This page covers only the sizes Solo lists on its own website.
How to measure a drink in a Solo cup
Since today's cups have no lines, you can add your own. Pour 1 cup of water from a measuring cup into an empty Solo cup, mark the level on the outside with a marker, then add another cup and mark again.
The first mark shows 8 fl oz and the second shows 16 fl oz. The second mark sits below the rim, because the whole cup holds a quarter cup more than two cups. For other amounts, the ounces to cups converter does the math.
How many Solo cups does a bottle fill?
| Container | Size | Solo cups |
|---|---|---|
| Two-liter bottle | 2 L | 3.8 |
| Half gallon | 0.5 gal | 3.6 |
| US gallon | 1 gal | 7.1 |
Solo cup: questions
Is a red Solo cup 8 oz?
No. One US measuring cup is 8 fl oz, and a red Solo cup holds more than twice that.
Is a red Solo cup 12 or 16 oz?
Neither, going by Solo's product page, which lists the red party cup at 18 fl oz. The 12 fl oz figure matches the top line on the original cup, not the size of the cup. If your cup says 16 fl oz, it is a different product, so go by its package.
Is a red Solo cup equal to 2 cups?
A little more. The cup holds 2.25 cups, so two measuring cups of water leave some room at the top.
Are red Solo cups 18 oz?
Yes. Solo lists its current red party cup, with the newer SOLO Squared design, at that size, and it says the original cup from the 1970s was the same size.
Related
Sources
Sources: Unit definitions: NIST Handbook 44 · Last reviewed · Report an error
https://howmanyounces.com/how-many-ounces-in-a-solo-cup/