Why We Recommend This Product?
  • Effectiveness
  • Portability
  • Appearance
  • Usability
  • Cost


The Grayl Ultralight Water Purifier is, as its name says, ultra light and the perfect companion for travelers who don’t want big bulgy water purifier flasks hoarding up space in their already filled-to-the-brim bag containing essentials. But rest assured that a water purifier is also essential, especially a Grayl model one which provides the best quality water purification you can find. Some might scoff at the relatively low capacity of the model and also at the hard labor needed to use it.


  • Lightweight and thus extremely portable
  • Extremely effective; takes care of bacteria, virus, sediments, metals
  • Is a priceless substitute for plastic, and the company also gives 1% of the profits to environmental non-profits


  • Has a low water capacity of 16 oz.
  • Takes a relatively long time to press

Water purifiers come in many types. There are the large water filter tanks and purifier systems, and then there are bottle or flask-like water purifiers perfect for the traveler/hiker. Grayl Ultralight Water Purifier is among the latter type.

Whether you love to travel or just have a habit of buying bottled water, we have a priceless alternative for you: try this product. It is not only effective in filtering your water to make it safe to drink and tasty too, but it will also save the environment as a plastic substitute. What’s more, it will save you the hassle of stocking up on bottled water.

Who Needs This Product?

Anyone would benefit from a water purifier bottle on which to rely for emergencies (like problems with the municipal water supply). But specifically speaking, we would highly recommend this to travelers, hikers, and adventurers. Whether you are exploring some forest or trekking a hill or just having an adventurous picnic, the Grayl Ultralight Water Purifier would do you good.

Why We Recommend This Product


The proof is in the pudding. We mean the proof is in the title: it is ultra light. The exact capacity of water it can carry is 16 oz, or less than half a liter. Moreover, it is compact in size. This means that the magical cylinder with the power of purifying your water can fit easily in your backpack, even in the side pockets.


Not only is the design compact and highly portable, it is also quite attractive as far as water purifier bottles go, and is award-winning. We personally dig the Coyote Amber colored product. Keep in mind that the color options have slightly different price.

Why We Recommend This Product?


Ever since Grayl has come into the business of producing water purifiers, it has aimed straight to the top. The efficacy of its purifiers is not only top-notch but simply the best. Reviewers far and wide have given rave reviews about the effectiveness of the filtration system of the water purifier.

We previously said that the product is magical, did we? Well, it’s all science actually, but it is wondrous how Grayl Ultralight Water Purifier is such a good water purifier despite being manual. Yes, it isn’t a big water tank with sophisticated mechanisms, and still it takes care of many, many impurities in water that other purifiers can’t.

True! Grayl Ultralight Water Purifier filters the following:

  • sediments (visible impurities in water such as sand and dust)
  • bacteria
  • many chemicals (like chlorine)
  • metals (such as aluminium)
  • bad odor (and makes water tasty in the process)
  • virus

The fact that Grayl Ultralight Water Purifier fights virus too is incredible, as most filters don’t do that.


We feel that the Grayl Ultralight Water Purifier is a bit difficult to use, but many water purifier bottles are like that. It does not make use of any electronic mechanisms, nor does it require sucking and chemical reactions like some water purifiers do. Yes! Some purifiers require you to lie flat on your belly and suck the lid.

No hassle like that with this product! Instead, the user has to press down – hard, with all your body weight! – to filter the water you put inside the water purifier.


The most important and far-reaching consequence of using a water purifier is that plastic pollution is reduced. Yes, bottle water made of plastic containers are cheap. And water purifiers made of plastic are no seemingly cost at all. But on the long run, the costs pile up, and in a month will accumulate to the cost of a water purifier.

Even if the cost of a good water purifier like Grayl Ultralight Water Purifier is not budget-friendly even as the substitute for plastic water bottles, the thing you should keep in mind is that you are serving the environment.

That’s what water purifiers do. However, Grayl Water Purifiers go a step beyond! Grayl is a member of “1% For The Planet”, which means that 1% of profits go to non-profit environmental organizations.

How It Works

As mentioned, Grayl Ultralight Water Purifier works manually. It works like a French coffee press. Yeah, you need to press the plunger. The more impure the water is, the harder will it be to filter it, and the harder will it be to press. In other words, if you have filled your Grayl Ultralight flask with dark and grimy water, then you have to push really hard.

How It Works

This is a disadvantage of the product as it takes a lot of effort to filter extremely dirty water. However, don’t be scared. Grayl Ultralight Water Purifier is known to be an excellent purifier, and if you are an adult, you can most probably be able to use it.

How long do you have to press? Well, the Amazon description says that 15 seconds of pressing will get you the whole 16 oz (the full capacity of the filter cartridge). How is it when compared to other water purifiers? Well, there are better and bigger water purifiers such as another of Grayl’s products: GRAYL Geopress 24 oz Water Purifier.

Still, pressing for 15 seconds is well worth the reward of getting amazingly purified water. Again, keep in mind that the time needed for pressing will depend on how dirty the water is. It can go upwards to 40 seconds of pressing. Moreover, as your water purifier ages, the time needed will also increase. Still, Grayl Ultralight Water Purifier will give you well above average service for years to come.

Alternative Choice

If you are really into traveling, and are planning long adventures or treks, you might find the capacity of the product to be meager. 16 oz. is like 2 cups of water. This will probably be enough for you at one go, as the quantity isn’t low by any means. However, for bigger and longer journeys, many people prefer a bigger capacity. If you are among them, then we might suggest you an alternative suggestion:

Not only does the Geopress have a bigger capacity of 24 oz, it is also faster to use (works within 8-10 seconds of pressing). However, it is obviously larger in size, and this very well may be a bigger turn-off for travelers than lesser capacity. It is honestly up to the customer whether he or she would like to compromise portability for efficiency.

Frequently Asked Questions (FAQs)

1. What is the weight of the Grayl Ultralight Water Purifier?

The Grayl Ultralight Water Purifier weighs 309 g, or 10.9 oz. when it is empty.

2. What capacity does the Grayl Ultralight Water Purifier have?

The Grayl Ultralight Water Purifier has a capacity of 16 oz. That is almost half a liter.

3. What is the flow rate of Grayl Ultralight Water Purifier?

The Grayl Ultralight Water Purifier has a flow rate of 16 oz. per 15 seconds. However, this is to be taken as a hopeful average. When the water is significantly dirty, like if it is blackish or reddish in color or has sand and metals, then the pressing will take more time and be more laborious.

4. How long will the Grayl Ultralight Water Purifier last?

The Grayl Ultralight Water Purifier cartridge filter has a shelf life of 300 uses. That means 150 liters or 40 gallons. And when the cartridge filter is used to such extent, it can be replaced! Yes, you don’t have to buy the whole product.

5. How often should I do maintenance on the Grayl Ultralight Water Purifier?

We recommend doing maintenance on it weekly. Why so often? That’s because the water purifier is probably being used often, especially if you are on a journey. If not taken care of, then it will smell, and the filter will get clogged.

For maintenance, you should leave open the filters after cleaning them and expose them to sunlight so that they dry. This will prevent any odor from developing. Moreover, check for any damage or leakage of the product.

Final Words

A water purifier flask is a traveler’s best friend, really. We can’t imagine going on treks or adventures without a reliable water purifier in our bags to prevent having to drink out of unhygienic streams and other places. After reading this Grayl Ultralight Water Purifier review, you now know there are seldom water purifiers as reliable as this product – its chief advantages being portability and effectiveness.

Know how to make your trip and your water purifier even more reliable? Why, just pack a replacement filter or a collapsible bottle just in case!

Last update on 2023-12-08 / Affiliate links / Images from Amazon Product Advertising API. WaterFilterly is user-supported. We might receive a commission on any purchase you make through clicking links on this page.

Similar Posts


  1. The post discusses the various types of water purifiers available in the market. It does not provide any specific information about each type or their pros and cons.

    In my opinion, it would have been helpful if the post had provided more details about each type of water purifier, such as how they work, their effectiveness in removing contaminants, and their cost. Additionally, it would have been beneficial to include recommendations or considerations for choosing the right water purifier based on individual needs and preferences.

  2. When it comes to choosing a water purifier, it’s important to consider the specific needs of your household. Different types of water purifiers offer various benefits and features. Here are a few popular types of water purifiers:

    1. Reverse Osmosis (RO) Systems: These systems use a semipermeable membrane to remove impurities and contaminants from water. RO systems are effective in removing dissolved solids, heavy metals, and chemicals.

    2. Activated Carbon Filters: These filters use activated

  3. While it is true that water purifiers come in many types, it is important to consider the drawbacks and limitations of these devices. The author fails to mention that not all water purifiers are created equal and some may not effectively remove all contaminants from the water.

    For instance, while activated carbon filters are commonly used in water purifiers, they are not effective in removing certain contaminants like heavy metals and fluoride. Reverse osmosis systems, on the other hand, can remove a wide range of contaminants but

Leave a Reply

Your email address will not be published. Required fields are marked *