How many ounces in a glass?
1 glass of water = 8 fl oz
by custom, not by definition · 1 cup · 237 mL · wine pour 5 fl oz · beer 12 fl oz · pint glass 16 fl oz
Converter
Common amounts in fl oz
Type a number, like 1 1/2 or 0.75.
Other cup standards
US cups: 1 · nutrition-label cups (240 mL): 0.986 · metric cups (250 mL): 0.946 · UK fluid ounces: 8.33
A glass is not a unit of measure, so the answer depends on the glass. When advice or a recipe counts glasses of water, it means 8 US fluid ounces: one measuring cup, about 237 mL. Eight of those glasses add up to 64 fl oz, which is a half gallon or about 1.89 liters.
The glasses in your cupboard can hold less or more than that. To find out, fill one from a measuring cup and count. For drinks, the US National Institute on Alcohol Abuse and Alcoholism describes a standard drink as 12 fl oz of regular beer, 5 fl oz of table wine or a 1.5 fl oz shot of distilled spirits.
A US pint glass filled to the rim holds 16 fl oz, or 2 cups. A British pint glass holds 20 imperial fl oz, about 19.2 US fl oz. More on each size at cups in a pint, 5 oz to cups and 12 oz to cups.
| Glass | US fl oz | Cups | mL |
|---|---|---|---|
| Glass of water, as in "8 glasses a day" | 8 | 1 | 237 |
| Standard glass of wine | 5 | 5/8 | 148 |
| Standard beer (can or bottle) | 12 | 1 1/2 | 355 |
| US pint glass, full | 16 | 2 | 473 |
| UK pint glass (20 imperial fl oz) | 19.2 | 2.4 | 568 |
| Shot glass | 1.5 | 3 Tbsp | 44 |
| Glasses | US fl oz | Cups | Liters |
|---|---|---|---|
| 1 | 8 | 1 | 0.24 |
| 2 | 16 | 2 | 0.47 |
| 3 | 24 | 3 | 0.71 |
| 4 | 32 | 4 | 0.95 |
| 6 | 48 | 6 | 1.42 |
| 8 | 64 | 8 | 1.89 |
| 10 | 80 | 10 | 2.37 |
| 12 | 96 | 12 | 2.84 |
| 16 | 128 | 16 | 3.79 |
| Container | US fl oz | 8 fl oz glasses |
|---|---|---|
| 16.9 fl oz bottle (500 mL) | 16.9 | 2.11 |
| 1 liter | 33.8 | 4.23 |
| 2 liters | 67.6 | 8.45 |
| Half gallon | 64 | 8 |
| 1 gallon | 128 | 16 |
Wine, beer and shot sizes: NIAAA, "What Is a Standard Drink?" (consulted 2026-11-10).
How many 8 oz glasses are in 2 liters?
About 8.45 glasses. Two liters is 67.6 US fl oz, and each glass is 8. One liter fills about 4.23 glasses and a US gallon exactly 16. See cups in a liter for other bottle sizes.
How many mL is a glass of water?
An 8 fl oz glass is 236.6 mL, usually rounded to 237 mL. US nutrition labels round a cup to 240 mL, and countries that cook with metric cups use 250 mL, so a "glass" in a metric recipe is slightly larger.
Questions
How many ounces in a glass of water?
8 US fl oz when "a glass" is used as a measure, the same as 1 cup. Real drinking glasses vary.
How many ounces in a glass of beer?
A standard US beer is 12 fl oz (NIAAA). A US pint glass holds 16 fl oz.
How many ounces in a glass of wine?
A standard pour is 5 fl oz (NIAAA), a little over 1/2 cup.
How many ounces is 8 glasses of water?
64 fl oz, which is 8 cups, a half gallon or about 1.89 liters.
By Alton Vieira · Updated . Sources: US customary units: NIST Handbook 44. How we calculate.