Hydro Flask bottles come in many different shapes and sizes and are usually measured in US ounces.
So how many Hydro Flasks bottles does it take to make a gallon or to make a liter?
It takes 4 bottles of 32 oz Hydro Flasks to make a Gallon, 6.4 bottles of the 20 oz and 5.3 bottles of the 24 oz size. The 64 oz Hydro Flask is half a gallon and the 128 oz Hydro Flask is a full gallon. The 32 oz is closest to 1 Liter at 946 mL.
Below is a table showing the different sized Hydro Flasks as well as their volume in mL and how many of each bottle you need to make a full gallon or liter:
| Size Hydro Flask | Volume in mL | Bottles Required To Make a Gallon | Bottles Required To Make a Liter |
| 12 oz | 355 mL | 10.7 | 2.82 |
| 16 oz | 473 mL | 8 | 2.11 |
| 18 oz | 532 mL | 7.1 | 1.88 |
| 20 oz | 592 mL | 6.4 | 1.69 |
| 21 oz | 621 mL | 6.1 | 1.61 |
| 24 oz | 710 mL | 5.3 | 1.41 |
| 25 oz | 749 mL | 5.1 | 1.34 |
| 32 oz | 946 mL | 4 | 1.06 |
| 40 oz | 1,182 mL | 3.2 | 0.85 |
| 64 oz | 1,892 mL | 2 | 0.53 |
| 128 oz | 3,785 mL | 1 | 0.26 |
Get Yourself a Hydro Flask
Hydro Flasks are a great way to help yourself drink more water and they can keep water ice cold for up to 24+ hours.
Click here to see the latest prices of Hydro Flasks at Amazon
