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How many bottles of water should I drink a day?
Divide your daily ounces by the size of your bottle. A common rule of thumb for a 150 pound adult is 75 ounces, which is about 4.4 bottles of 16.9 ounces, 3.1 bottles of 24 ounces or 2.2 bottles of 1 liter. Enter your weight or an amount above to see your own count, and the table under the result lists every bottle size.
How many cups of water a day?
Divide your ounces by 8. The popular 8 cups a day is 64 ounces, about 1.9 liters. A rule of thumb of 75 ounces for a 150 pound adult is 9.5 cups, shown to the nearest half cup.
How many glasses of water a day?
On this page a glass is 8 fluid ounces, the same as a US cup, so glasses and cups match. A larger glass holds more than 8 ounces, so count by ounces if you can.
The 8 glasses a day idea
Eight 8-ounce glasses is 64 ounces. It is a popular rule of thumb with an unclear origin, not a research-based requirement, and it ignores body size: see water intake by weight, where 200 pounds gives 100 ounces. Food and other drinks also add water. For a general guide, read how much water to drink a day, and for a full gallon, see water bottles in a gallon.
Bottles by size
How many bottles each daily amount takes, for each bottle size.
| Daily oz | L | Cups | 12 fl oz | 16.9 fl oz (500 mL) | 20 fl oz | 24 fl oz | 32 fl oz | 1 L |
|---|---|---|---|---|---|---|---|---|
| 48 | 1.4 | 6 | 4.0 | 2.8 | 2.4 | 2.0 | 1.5 | 1.4 |
| 64 | 1.9 | 8 | 5.3 | 3.8 | 3.2 | 2.7 | 2.0 | 1.9 |
| 75 | 2.2 | 9.5 | 6.3 | 4.4 | 3.8 | 3.1 | 2.3 | 2.2 |
| 80 | 2.4 | 10 | 6.7 | 4.7 | 4.0 | 3.3 | 2.5 | 2.4 |
| 96 | 2.8 | 12 | 8.0 | 5.7 | 4.8 | 4.0 | 3.0 | 2.8 |
| 100 | 3.0 | 12.5 | 8.3 | 5.9 | 5.0 | 4.2 | 3.1 | 3.0 |
| 128 | 3.8 | 16 | 10.7 | 7.6 | 6.4 | 5.3 | 4.0 | 3.8 |
Frequently asked questions
How many bottles of water should I drink a day?
It depends on your estimate and bottle size. A common rule of thumb for a 150 pound adult is 75 ounces, which is about 4.4 bottles of 16.9 ounces (500 mL). A 24 ounce bottle would take about 3.1 bottles. Enter your weight and bottle size above for your own count.
How many cups of water should I drink a day?
Divide your daily ounces by 8. A common rule of thumb for a 150 pound adult is 75 ounces, which is about 9.5 cups. The popular 8 cups a day is 64 ounces, or about 1.9 liters. Your number can be higher or lower, so use the weight box above to see your own.
How many glasses of water a day?
A glass here means 8 ounces, the same as a US cup, so glasses and cups match. Eight glasses is 64 ounces. A 150 pound adult's rule of thumb estimate is 75 ounces, about 9.5 glasses. Larger glasses hold more than 8 ounces, so count by ounces if you can.
Is 8 glasses of water a day enough?
Eight 8-ounce glasses is 64 ounces, a handy round number and not a rule that fits everyone. Body size, exercise and climate move the amount up or down: a 200 pound adult's rule of thumb is 100 ounces. Food and other drinks also add water, so ask your doctor what is right for you.
Is 500 mL of water a day enough?
500 mL is about 17 ounces, roughly one small 16.9 ounce bottle. That is well below the general estimates on this site, such as 75 ounces for a 150 pound adult. Other drinks and food add water too, but if you often drink very little, ask your doctor what is right for you.
How many bottles is 2.5 liters of water?
2.5 liters is about 85 ounces, which is about 5.0 bottles of 16.9 ounces, or 10.5 cups. With 24 ounce bottles it is about 3.5 bottles. Choose your bottle size above and enter your weight to see a count that fits your own estimate.