Hydro Flask vs. Klean Klanten Review (2020)

We may receive compensation from the companies whose products we review if you click through our affiliate links. As an Amazon Associate we earn from qualifying purchases.

To an everyday user, a flask that can keep your water hot or cold for 2 hours is seen as a big feat. But to a hiker, traveler, or your little one in school, more is needed. While having a flask that can preserve your water for 3 hours isn’t a bad idea, it’s an unacceptable standard in the insulation world. A move that shows how far the industry has come.

Presently, several insulated flasks are making round in the market that it becomes almost impossible to choose one. From Hydro Flask to Klean Klanten and Yeti. They all have exceptional design, not to mention their enhanced insulating property that can preserve your ice for as long as 24 hours.

If the insulation world were in show business, Hydro Flask would be the popular celebrity that steals the spotlight on the red carpet. While the comparison seems a bit exaggerated, Hydro flask has received special attention in the real world. It’s the choice of everyday people as well as celebrities. However, does that make it the best insulation bottle to buy?

Or is it overrated? In this article, we will compare the most popular insulated bottle against the critic’s choice: The Klean Klanten. If you’re thinking of getting a new bottle, these two will always pop-up on the list of best-insulated bottles on Google. Hence, we’ve decided to compare their components against one another to answer the ultimate question – Klean Kanteen or Hydro flask: Which should you buy?

Hydro Flask vs. Klean Kanteen: Which Should You Buy?


Before buying any flask, you want to make sure it has enough depth to hold a large volume of water. The outlook of the bottle sways most buyers, but this is nothing compared to its insulation and cap design. In terms of volume, Klean Kanteen has several variations. The most popular versions are 12, 16, or 20 Oz. This is a little negative, given the amount of water needed on a daily basis.

If you’re to go for either of the options listed above, it will be for your little one. Even with that, it’s hard enough to quench their thirst all through the day. Hence, you have to make a better choice if you’re embarking on a road trip or hiking. You will be left disappointed if you decide to go for the Klean Kanteen.

Coming to Hydro flask, the volume is far more impressive. The smallest bottle from this brand happens to be 18 Oz while there are other bigger options like the 32, 40, and 64 Oz. From Experience, the 64 Oz bottle will be hard to move around.

Which explains why most people prefer to go for either the 30 or 40 Oz. This is understandable because both bottles are less bulky and hold enough water to keep you through your activities.

If you’re planning on getting a new flask, the volume is one area you should critically pay attention to. Hence, if you’re to consider the volume of the two products, we consider the 32 Oz hydro flask bottle and the 20 Oz Klean Kanteen bottle to be the most convenient of all the bottle sizes available. Except if, of course, you want a bottle that can store water for later use in the kitchen. Then the 60 Oz bottle will come handy.

Ease of Use

In terms of usage, it’s worth mentioning that both bottles are insulated, making them ideal for preserving both hot and cold drinks. They come in different shapes and sizes. The width of the mouth, making a lot of difference.

If I would like to take tea at work, the size of the mouth becomes negligible. It doesn’t matter whether the mouth is wide or narrow; your tea will always pour out without any restrictions. However, if you want a bottle to preserve your ice, going for a bigger mouth will be better. Thus it will allow you to throw in bigger chunks of ice. Fortunately, Hydro Flask provides a lot of options to choose from.


Since most folks hardly use an insulated flask for water alone, we’re going to assume that you will be using the bottle for beverages, as well. A splash might not be an issue if you will be using it to store water, but for colored substances like beer or milk, it’s bound to get sticky on the body, which isn’t a pleasant sight.

The interior of both flasks could be a bit dark that you might struggle to keep track of the content poured into the bottle. Ensure they’re not filled to the brim as the content might splash on the body when the cap is installed. Since both flasks are made from stainless steel, a splash might make it hard to grab the bottle.

In addition to that, you might be tempted to throw the bottle into a dishwasher, but that isn’t needed. The exterior of the Hydro flask is coated. Hence, it should be hand washed with soapy water.

The manufacturer of Klean Kanteen says the bottles are dishwasher safe. This is hard to contend with since the company has bottles that aren’t coated. However, if any of the flasks you purchase is polished in any way, ignore the manufacturer’s instructions and stay clear of a dishwasher if you want to use your bottle in the long run.


If you’ve used a Flask with a small mouth, you will notice how easy it is to pour water when you’re moving. If you’re riding a bike or jogging, the bottle is placed higher up that it becomes hard for the content to pour out against your movement. Hence, if you will be doing a lot of sporting activities, you should get a flask with a wider mouth.

Hydro Flask has a double-wall vacuum that’s serenaded by a wide mouth that’s 2.28 inches in width. Klean Kanteen comes with an insulated cap that’s 2.125 inches; the difference between both is barely 1, which isn’t noticeable.

The insulated cap of Klean Kanteen gives it an edge over Hydro flask. Rapid heat loss is experienced through the cap, but having it insulated reduces heat transfer. Going by this, it is guaranteed that the Klean Kanteen will do a better job at making your water hot for long hours.

In certain climes, bottles with the wider mouths are favored since they’re easy to drink from, but that’s just a personal opinion. There are some negatives to having a wide mouth bottle, but it all comes down to what every individual wants. Since bottles with wider mouth pour easily, it’s almost impossible to have a nice sip from a hot drink. You try to take a sip but find the drink rushing out to the point that you accidentally burn your tongue.

In addition, bottles with a wide mouth are easy to clean compared to those with narrow mouths. You will struggle to clean the angles around the narrow mouth. If there’s a sticky content like beer or milk poured in, it will be hard to clean.


As earlier mentioned, it’s hard to see any reason that guarantees both bottles to be dishwasher safe. Both brands have colored bottles, but the width of the mouth could be a huge pain when cleaning. Your hands might be too large to reach underneath the bottle, which is a big letdown if you have sticky content.

Hence, if you will struggle to reach all its angles on your own, I don’t see a dishwasher doing a better job. The Hydro flask is mostly coated, and throwing in a dishwasher will dent the powder coating.

Coming to the Hydro flask, none of the bottles is dishwasher safe, but Klean Kanteen bottles have those that aren’t coated, making them safe for your dishwasher. If it’s neither insulated nor coated, it’s always good to wash in the dishwasher, but the narrow mouth will come as a limitation.

You might see instances where individual manufacturers will claim both bottles are dishwasher safe. This is just a way of making their products acceptable by the public. Our conclusion is drawn from reviews from real buyers on Amazon.

Away from the bottles, the cap and lids of both bottles are safe to clean in a dishwasher. If you decide to hand-wash your bottle, just fill the bottle with soapy water and shake to get rid of any sticky substance underneath.


The number of hours ices can stay in without melting is an essential aspect of both flasks. Due to the size of the mouth of Hydro Flask, you will be able to throw in larger pieces of ice while you will struggle to fit in large chunks of ice through the narrow mouth of the Klean Kanteen.

This will obviously affect the result since small ice melts faster than large ones. Storing hot or cold water in these bottles won’t increase their temperature, and neither will your drink get colder. The reason is to ensure the ice melts slowly rather than rapidly.

In our previous test, the hydro Flask can keep your ice cold after 24 hours. At 24 hours mark, most parts of the ice would have melted, but there will still be small pieces of it left. Here, the double-wall vacuum of your Hydro flask seems to have an advantage.

Plus, both bottles are insulated, so the temperature of the interior won’t affect the outside body. Hence, don’t expect any form of condensation.


Hydro Flask and Klean Kanteen, in addition to Yeti have the best insulative property compared to other brands. Both brand comes with a double-walled vacuum and averages the same temperature when tested against hot and cold water.

The double-walled vessels are separated in the Hydro Flask. Which means you’re protected from the internal heat emitting from the flask. Since both products are made from stainless steel, the double-walled insulation is a way of reducing heat transfer to the surface.

The technology of Hydro Flask is formulated towards keeping icy drinks cold rather than preserving the temperature of cold water. Hence, it performs better when filled with cold water rather than hot water.

Since the cap isn’t insulated, heat transfer takes place at this point. Klean Kanteen has the edge over its rival in terms of keeping hot drinks hot for long hours. Klean Kanteen can comfortably preserve your hot water for 12 hours while Hydro flask will do so for 6 hours. At 6 hours mark, your water feels lukewarm, and anything beyond that, the temperature drops rapidly.

The performance of Klean Kanteen when used with cold water isn’t impressive. In essence, if you want a flask to keep your drink cold, go for Hydro flask, but if you want one that can keep your drink hot for long hours, Klean Kanteen will be the answer.


If you’re willing to spend $30 – $50 on a simple water bottle, then you’re going to want it to be perfect. Most importantly, you will hope to use it for long and, if possible, pass on to your kids if the need for a bigger one arises.

The material both products are built with determines whether it’s durable or not. As earlier mentioned, both bottles are built with stainless steel with Hydro flask spotting an additional coating. What this means is that the bottles are likely to come out well after mistakenly dropping on the floor.

If you put into frequent use, you will see a few dents as well as scratches, but this isn’t enough to result in leakage unless they collide against heavy objects. Coming to the lid, both bottles spot a plastic lid which is more susceptible to damages than the bottle.

Klean Kanteen cap is insulated. Hence extra care must be taken to ensure it isn’t damaged in any way as this will affect its insulating ability. While users have complained about the polish used on hydro Flask chipping off, Klean Kanteen bottle lids are said to be prone to leaks.

Cap, Lids, and Leaking

Cap design is one area Hydro flask is found wanting. It doesn’t have a nice grip. The handle is designed in a way you can only grip with just two fingers rather than three. Klean Kanteen has room for an extra finger, which makes it easier to use and swing around. What’s even worse is that it feels less durable due to constant use.

However, this isn’t enough reason to conclude that the latter is better than the former. Hydro flask comes with a few customization options that allow you to style your cap in different ways. It has an in-built feature that allows you to convert your cap to a sippy-style cup bottle, which is great if you use the bottle for sporting activities as it allows one-hand drinking.

Fortunately, Hydro flask comes with a lifetime warranty meaning a replacement can be gotten if the present one doesn’t meet your expectations.

The cap of both brands is leak-proof, but that of Klean Kanteen has an edge in terms of controlling the temperature of hot drinks since its insulated. Another thing is that none of Hydro flask or Klean Kanteen cap are dishwasher safe due to their designs.

A closer look at both caps shows that they can be used interchangeably, provided you find one that matches the mouth of your bottle.

Body Design

Looks alone aren’t the only criteria for choosing a nice flask, but it can be a deciding factor if you have two products that are similar to one another. Both brands have a lot of colors to choose from. They have nice finishes, and their various logos are placed in a way that makes heads turn. Whether you’re going for the plain steel or coated version of Klean Kanteen, the finish is always spectacular.

When it comes to color palette, Hydro flask has the widest spectrum in the industry. In terms of design, it’s surely a tie between these two. Their bottles are similar to one another except for the logos, which also happens to be written in the same font.


Both devices are compatible with backpacks and car cup holders. If otherwise, you can purchase the accessories compatible with your selected bottle from the brand.

Final Verdict

Both bottles are reasonably priced and are the best in terms of insulation. Some might go for Klean Kanteen since its a few penny less than Hydro flask, but what good is a flask prone to leaks? It would make sense to rather take a risk with Hydro Flask since it has a lifetime warranty.

Hydro flask is ahead in terms of durability, insulation, and stronger cap. Deciding on which flask is better isn’t a simple task. Even after going through each feature, the similarities are just hard to ignore. Hence, the deciding factor between these two will come down to individual needs.

If you want a small Flask to keep your coffee or water hot for long hours at the office, you would rather go for Klean Kanteen. However, if you want something with more depth, capable of keeping your drink cold when hiking or hitting the road, Hydro flask is the one for you.

More Outdoor Gear Reviews

Leave a Comment