How Many Cups Are In a Water Bottle? It Depends

How Many Cups Are In a Water Bottle? It Depends

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With many health sites publishing recommendations for water intake per day, usually measured in cups, consumers are often confused about how to determine if they’re getting enough water.

The fact that water bottles also have different sizes, and many don’t publish a Nutrition Facts label, can make it challenging to ensure proper hydration.

So how many cups of water are in a water bottle? Does it depend on the brand? And how many cups of water should you drink for optimal health?

In this article we’ll answer these questions by breaking down the number of cups in some of the most popular water bottle brands and sharing our thoughts on whether there's an optimal number of cups to drink daily for good health.

How Many Cups in Water Bottles by Brand

Most bottled water is measured in ounces (oz), and 1 oz = 0.125 cups. Here's a breakdown of the number of cups of water in some of the most popular bottled water brands:

Standard glass of water (8 oz) - 1 cup

Fiji (regular size) - 2.1 cups

LIFEWTR - 2.1 cups

Essentia - 2.5 cups

Core - 3.8 cups

Flow - 4.2 cups

Certain brands like Poland Spring, SmartWater and Evian sell so many variations of water bottles that we can’t provide a general answer.

With the formula above, it's possible to calculate the number of cups in any water bottle. Just multiply the number of ounces in that water brand by 0.125 to get the number of cups.

Do You Really Need 8 Cups of Water Per Day?

One of the main reasons that people analyze how many cups of water are in water bottles is because there's a popular health philosophy that 8 cups of water per day can improve health.

But is this really true? A TedTalk with over 500,000 views features a doctor analyzing this trend to determine if it's legit:

How to Stay Hydrated Without Checking Cups

Rather than purchasing bottled water which is a waste of money, is harmful to the environment and is potentially harmful to human health due to the proven estrogenic effects of single-use plastics, we recommend purchasing a reusable, stainless steel water bottle with time markings.

The Venture Pal insulated water bottle is made entirely from stainless steel so there's no risk of plastic chemicals leaching into the water. It's 32 oz, which equates to 4 cups of water. This makes it easy for consumers to ensure they're getting a minimum of 8 cups per day (if that's their goal). Just drink two fills of the water bottle per day.

In our opinion, using a large reusable water bottle is the healthiest and most convenient way to stay hydrated, because it only needs to be filled twice per day and allows you to use filtered water rather than water of questionable purity from a bottled water brand.

Interested consumers can check out the Venture Pal stainless steel water bottle at this link to the product's Amazon listing.

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The number of cups in a water bottle depends significantly on the water bottle brand. It's possible to calculate the number of cups in any water bottle with a simple formula: multiply the number of ounces by 0.125.

There doesn't seem to be much scientific evidence suggesting that eight cups of water per day optimizes health, or that there is any magic number of cups. The number of cups of water someone needs to stay optimally hydrated will vary significantly from person-to-person based on things like weight, sex and exercise.

We believe the best way to stay hydrated, from both a cost and health perspective, is to purchase a reusable plastic-free water bottle. The water bottle brand we recommend holds exactly 4 cups worth of water, so it makes it easy for a consumer to drink the exact number of cups of water per day they're aiming for.