How Many Cups of Water Are in a Water Bottle?


5 Owala water bottles cascading in a diagonal line.


Are you trying to cut down on your plastic water bottle usage? Doing so is a good idea, since Americans purchase 50 billion water bottles yearly!

One of the best ways to cut down on plastic water bottles is to buy a refillable water bottle. But you may notice they come in a whole lot of sizes. You're probably asking questions such as, how many cups of water are in a water bottle? Let’s answer this question and explain why water bottle sizes matter in this guide.

About Water Bottle Sizes

Water bottles are available in different sizes based on need and preference. Some people may keep a refillable water bottle at their desk or in their car to sip throughout the day.

Someone who works remotely or at a desk job may not care as much about having a large water bottle since they can refill their water bottle as they need. But someone who drives constantly or works a demanding job may prefer buying a giant bottle so there’s always water at hand. Fitness enthusiasts may also want a larger water bottle to take to the gym or out on a jog.

On the other end, kids' water bottles are available in smaller sizes since children don't need to drink as much water. Parents may fill up the water bottle and pack it in their lunch box, so kids can drink water instead of sugary drinks. The smaller size also makes it easier for kids to hold the bottle themselves.

How Many Cups of Water Are in a Water Bottle?

To answer this question, we first have to discuss the difference between cups and ounces.

Most sellers have their water bottles listed in ounces and not cups. There are different reasons why a seller may do this, but measuring in ounces is more popular since water is liquid. (Thank you, science classes.) While cups are commonly used to measure liquid in the US, they also measure solid foods. A seller may use ounces to take away any confusion about their product—that it's only used for liquid and not solid food.

With that being said, how do you know how many cups are in your water bottle if the measurement is in ounces? It takes simple math to figure this out: 8 ounces = one cup.

To figure out how many cups are in your water bottle, divide the ounces by 8 to find out the cups. And hey, if you don’t want to do the math, we’ve got your back. Here's a breakdown of common water bottle sizes in ounces and their cup equivalents:

  • 19 ounces = about 2.4 cups
  • 24 ounces = 3 cups
  • 32 ounces = 4 cups
  • 40 ounces = 5 cups

Use this formula to decide which water bottle size is right for you. If you're still unsure, don’t worry! We’llll chat about daily recommended water intake requirements in another section.

Water Bottle Sizes for Kids

You may have noticed that kids' water bottles hold less water than the average adult's. Kids' water bottles are typically 14 ounces (14 ounces = 1.75 cups), though some may be smaller.

There are a few reasons why. First, kids' hands are tiny, and a smaller bottle is easier for them to grab, hold, and carry water. The smaller lid is also easier for them to open. Plus, kids also don't need to drink as much water as adults—which brings us to our next section.

Why Is Water Bottle Size Important?

While water bottle size can fit different lifestyles and preferences, it's important to know your water bottle size. Why? To ensure you drink enough water daily.

The average adult needs to drink a half-gallon of water every day and a gallon of water for those who are more active. Our guide dives deeper into how many water bottles make a gallon. However a gallon can be intimidating, so let’s break a half-gallon of water down. A half gallon equals 8 cups, which also equals 64 ounces. 

Say you purchase a 32 oz water bottle, which equals 4 cups. You need to drink two of those a day to get your daily water consumption. Easy peasy. Drinking two water bottles is a lot easier to remember than multiple mathematical formulas. 

This is also important for kids. The amount of water the average child needs depends on their age. Here is  what’s recommended:

  • 1-3 years of age: 4 cups (32 ounces)
  • 4-8 years of age: 5 cups (40 ounces)
  • Older than 8 years of age: 7-8 cups (56-64 ounces) 

Keep in mind that milk is also included in this figure for toddlers (1-3 years old).

So if you purchase a 14 oz water bottle for your nine-year-old, they’ll need to drink at least four bottles to get their daily recommended water intake.

Benefits of Drinking Enough Water Daily

We've always been told to drink enough water every day. But why is this important?

Flushes Toxins

Toxins can mean many things. They can be bacteria or viruses that enter our body, or they can be waste products that our body naturally produces. No matter the type, toxins can cause adverse effects such as lack of energy, accelerated aging, and even the failure of normal bodily functions. Scary, right?

When you drink enough water, these fluids will flush out harmful toxins in your body. You'll not only feel better, but your body will perform to its full potential.

Improved Joint Function

Did you know that as much as 80% of your joint cartilage is made of water? When you consume enough water, your bone-against-bone movement will feel smoother. Your joints will also have more flexibility, which will improve your range of movement (hello, karake chop kicks).So if you want to keep your joints lubricated and prevent joint pain and inflammation, drink up! Brain Health

Water also makes up 75% of your brain. This means dehydration takes a toll on your brain health. If you’ve ever had a brain fog, you know what we’re talking about. So be sure to drink throughout the day to help you think coherently, improve concentration, enhance memory, increase brain cell communication, better perform on cognition tests, make faster decisions, and more.

Weight Loss

We've always been told to drink water to lose weight, and there's a reason why. Switching out water for unhealthy beverages such as soda decreases sugar and calorie intake. If you drink water before and with meals, it can help suppress your appetite. Drinking water throughout the day can also help you feel fuller, resisting the urge to snack—as delicious as those cookies and chips are

Use Refillable Water Bottles

Now that you know how many cups of water are in a water bottle, you may wonder why you should use refillable water bottles. The production of single-use plastic water bottles uses fossil fuels, which causes pollution.

Refillable water bottles don't use these dangerous fossil fuels during the production process, so you're making an environmentally conscious choice. High five! Plus, many refillable water bottles are insulated, so they stay cool.

Are you looking for a refillable water bottle? Shop our selection today.