A 64 oz water bottle holds 64 US fluid ounces — exactly a half-gallon, 8 cups, or about 1.893 liters.
For the full breakdown, see our best 64 oz Water Bottles guide.
Half a gallon of water in one container sounds simple until you try to fit it in a cup holder or under a faucet. The hard part is that “64 oz” describes volume only, and the physical bottle built around that volume changes shape dramatically depending on the brand and whether it’s insulated.
What 64 Ounces Actually Means in Cups and Liters
Sixty-four US fluid ounces equals 8 cups, a half-gallon, and roughly 1.893 liters. Those are the same amount of liquid in different units, and they match the standard US liquid-volume naming you’ll see on grocery shelves.
The unit itself trips people up more than the math. A “64 oz” label refers to fluid ounces, a measure of volume, not weight ounces, a measure of mass. That distinction matters when a product description just says “oz” without specifying which kind.
How Tall and Wide Is a 64 Oz Bottle?
A 64 oz bottle isn’t one standard size — height ranges from about 9.8 inches to roughly 12.6 inches, and width from about 4.0 to 5.5 inches, depending on the material and insulation.
Stainless-steel models cluster fairly tightly.
Plastic and glass versions spread wider. Glass and plastic models generally land around 10.75 to 12.6 inches tall and 4.0 to 5.5 inches wide.
| Bottle Model | Dimensions (H x W) | Weight |
|---|---|---|
| Klean Kanteen 64oz Wide Mouth (non-insulated) | 9.8 in x 4.34 in | 10.3 oz |
| Klean Kanteen 64oz TKWide with Loop Cap (insulated) | 11.25 in x 4.65 in | 29.5 oz |
| Klean Kanteen Recycled Stainless-Steel with Loop Cap | 9.8 in x 4.43 in | Not listed |
| Nalgene 64oz Growler (plastic) | Not listed | 8 oz |
| Typical glass models | 10.75–12.6 in x 4.0–5.5 in | Varies |
| Typical plastic models | 10.75–12.6 in x 4.0–5.5 in | Varies |
| Opening diameter (wide-mouth stainless) | 2.125–2.6 in | — |
One spec that quietly decides how usable a bottle is: opening diameter. That gap controls whether standard ice cubes drop in easily and which cleaning brushes and caps fit.
If you’re weighing specific models against each other, browsing a tested roundup of 64 oz water bottles saves a lot of spec-sheet cross-checking.
Why Measurements Vary So Much Between Brands
Two bottles can both say “64 oz” and still differ by nearly three inches in height, because brands build different shapes around the same internal volume.
Insulation is the biggest variable. Doubling up stainless walls with a vacuum gap adds bulk and mass, which is why the insulated Klean Kanteen TKWide tops out at 11.25 inches while the non-insulated version stays at 9.8 inches. Lid style adds height too — a loop cap, a straw lid, and a flat cap all change the overall measurement even on the same bottle body.
Retail listings make this harder by mixing measurement types. Some dimensions include the lid, some don’t. Some describe the bottle, some describe the shipping box. Before you buy, confirm whether the numbers cover the full assembled bottle and whether “oz” means fluid ounces of capacity. Both Klean Kanteen and Nalgene label capacity clearly on their product pages, which is the reliable place to check.
FAQs
Is 64 oz the same as a half-gallon?
Yes. In US liquid measure, 64 fluid ounces equals exactly half a gallon, which is also 8 cups or about 1.893 liters. Any bottle labeled 64 oz holds that same half-gallon volume regardless of its shape, height, or material.
Does a 64 oz bottle fit in a car cup holder?
Rarely. At roughly 4.0 to 5.5 inches wide, most 64 oz bottles exceed the 3-inch diameter of a standard cup holder. Large insulated models are the worst fit because their double walls push the width toward the upper end of that range.
How much does a full 64 oz bottle weigh?
References & Sources
- Klean Kanteen. “Water Bottle Wide Mouth 64 oz” Lists 64 fl oz capacity, 9.8 in x 4.34 in dimensions, and 2.125 in opening diameter.
- Nalgene. “64oz Growler” Confirms 64 oz volume, 8 oz weight, BPA/BPS-free construction, and leak-proof guarantee.
- REI. “Klean Kanteen Recycled Stainless-Steel Water Bottle with Loop Cap — 64 fl oz” Verifies 64 fluid-ounce capacity and 4.43 x 9.8 inch dimensions.

