The Best Portable Water Filters (Purification Pens)

Best Water Purification Pens

You’re out camping and you need water. There is a stream nearby. So, do you just grab the water, or do you make sure it’s clean? Of course, you will aim to make sure the water is absolutely clean. And how do you do it? With water a portable water filter, also known as purification pens.

After many hours of research and comparisons, we came to the conclusion that the best water purification pen currently on the market is the SteriPEN ULT-MP-EF.

The 5 Best Selling Water Purification Pens

For your convenience, the below list shows the 5 best selling water purification pens on The list is automatically updated once a day.

Among the smallest and most affordable pieces of purification technology, these pens are superb companions. They’re compact and incredibly efficient, so having one with you is always prudent.

Our Selection of The 5 Best Water Purification Pens:

If you have a need for one, you can check out our list of the best water purification pens, and maybe there will be something there that will catch your eye.

1. LifeStraw Personal Water Filter

LifeStraw Personal Water Filter

Our first item is the LifeStraw water filter pen/straw. Easy to use and highly reliable, this pen has been a favorite among adventurers of all kinds. The pen is simple to use – just pop the cap, put it in the water and start drinking – and that’s it.

The hollow fiber membrane filters out most 99.9% bacteria, protozoa, and viruses, making sure that the water you’re drinking is not in the least contaminated. The pen has a maximum capacity of 1000 liters.

2. SteriPen Ultra UV Water Purifier

SteriPen Ultra UV Water Purifier

Not all purifiers need filters, and SteriPen (you’ll get to see this name often) uses UV light to ensure that your water is clean and safe to drink. The purifier is very powerful, and it removes 99.9% of bacteria, viruses, and protozoa by killing them and disabling their reproduction. In fact, the device is just as efficient as the VitalityStraw water filter straw.

However, SteriPen has a much larger capacity, and it can go for 300 discharge cycles on a single charge, which is close to 15,000 liters purified. The battery is recharged via simple USB cable.

3. SteriPen Traveler Mini Water Purifier

SteriPen Traveler Mini Water Purifier

Like we said, you’ll see SteriPen a lot, and their Traveler Mini Water Purifier is a smaller, but equally powerful, iteration of the Ultra UV water purifier. This tiny pen is superbly effective against all the above-mentioned contaminants, delivering the same performance as both the Ultra UV and VitalityStraw. Not only that, but the UV does not leave an aftertaste, nor does it alter pH levels.

The only difference between this pen and the Ultra is that this pen is rated to 3000 liters, as opposed to Ultra’s 15,000.

4. Meco Water Filter Straw

Meco Water Filter Straw

Our penultimate product is another straw, this time from Meco. Just like VitalityStraw, this is a highly effective and simple device. It uses a hollow fiber membrane filter that retains up to 99.9% contaminants.

Of course, the device needs cleaning once in a while, and you can do it by simply backflushing. The straw is even more reliable than UV devices, as it requires no batteries. However, it has a lower capacity rating of up to 2000 liters.

5. SteriPen Adventurer Opti UV Water Purifier

SteriPen Adventurer Opti UV Water Purifier

Our last item comes again from SteriPen. This marvelous device uses UV light to destroy all contaminants, making any puddle of water as clean as a mountain spring. Not only that, but the UV light does not leave an aftertaste, nor does it change the pH value or other chemical traits of the water. The device is rated to purifying up to 8000 liters of water before requiring you to recharge it. It also doubles up as a flashlight.

Water Purification vs. Water Filters

Water filters are used to strain out particular types of bacteria. Water purification is used to remove bacteria that are generally too small to be caught in a filter.

Using a water filter will remove bacteria such as E.coli and salmonella, as well as protozoan cysts. A water purifier will remove viruses such as hepatitis A and norovirus.

Water filters work by using a physical barrier to remove particles from the water. Water purification uses various methods, including chemicals and ultraviolet light to kill viruses.

Size of Water Purification Pens

For adventure travel and hiking, then size is an essential factor. All the water purification pens featured in this review are compact and easily fit into a rucksack. 

Water Purification FAQs

How does Water Purification Work?

All water filters have an internal cartridge that catches microscopic debris and bacteria. Many purifiers also include this filter as the first stage, which improves the purifier’s effectiveness. One problem with a physical screen is that they will eventually get blocked. They need regular cleaning or replacement, following the manufacturer’s recommendations.

After passing through the filter, the purifier may use chemicals such as Iodine to kill bacteria. Another popular method is ultraviolet light. This has the advantage of not affecting the taste or PH rating of the water. The disadvantage of the UV method is that it requires batteries to operate.

What is the Most Popular Water Purification Technology?

Which water filter or purification method is most popular depends on the application. In this review, we are concentrating on purification pens designed for hiking and outdoor activities. For these applications, there are some restrictions, such as size and weight.

Water purification pens that use filters and chemicals are the most popular when hiking. There are several reasons for this;

  • Weight – When hiking, weight is at a premium and keeping it as low as possible is the aim
  • Size – Carrying space is limited when hiking
  • Purification method – Filter style water purifiers don’t need any additional items. Chemical water purifiers require you to carry a small container, while UV purifiers need batteries to operate and have the potential to stop working.
  • Where you are traveling – In more developed countries, a filter style water purifier will be sufficient. If you are going to remote areas in Africa, India, and similar countries, then a filter and chemical purifier are recommended.

The most popular water purification method for hikers is a combination of a filter and chemicals, as it removes the most potentially harmful contaminants. 

How Long will my Water Purification Pen Last?

Each water purification pen is different. The manufacturers will specify the number of liters of water that can be purified before you need to change something. 

The first part of your water purification pen that will need attention is the physical filter. This can quickly get blocked if the water you’re filtering is particularly dirty. 

If you know the water in the area you are traveling to has particularly dirty water, it may be useful to take a pre-filter with you. The pre-filter removes large particles from the water before going into the finer filter of the water purifier. Using a pre-filter will extend the life of your water purifier.

Steripen vs Lifestraw


The Steripen is an ultraviolet light device that kills microbes and bacteria in the water. It is quick and straightforward to use, giving you up to a liter of purified water with each use.

Simply push the button on the Steripen once for a half-liter and twice for a full liter. The UV light comes on, and you submerge the light wand in the water, gently agitating the water. After about a minute, the UV light turns off, and the Steripen flashes green if the process is complete or red if you need to repeat the purification. 


  • Easy. No need to carry large bottles of water with you, just purify as you need.
  • Great for hiking. The Steripen is very small and light. It will easily fit in your pocket.
  • Eco-friendly. The Steripen is an eco-friendly option as there are no chemicals or one-use plastic bottles involved, although you do need batteries.
  • Saves money. No need to buy expensive bottles of water when trekking, the Steripen can provide all you need, so long as you can find a water supply.


  • Particle lumps. If the water you want to purify is heavily contaminated with particles, then the Steripen may not be ideal. A separate pre-filter would be needed in this case.
  • Battery powered. The Steripen requires batteries to operate. It uses the small CR123 lithium batteries that are long-lasting, but without batteries, it does not work.
  • Price. Yes, the Steripen is not the cheapest option. You will need to weigh up the cost and maybe consider the LifeStraw instead.


In comparison to the Steripen, the LifeStraw is supremely simple. As the name suggests, it operates like a straw. Simply put the end of the straw in the water and suck to draw it through the filter and into your mouth. One of the benefits of this system is that you can drink directly from a river. You don’t even need a cup.

However, there are some drawbacks to its simplicity that make it less suitable for longer treks. 


  • Compact. As it is basically a rather thick straw, it easily fits into your rucksack. 
  • Lightweight. Consisting of just a hollow tube and a filter, the LifeStraw is very light.
  • Purification capacity. The microbiological filter will purify 4,000 liters of water before it needs replacing.
  • No batteries. Unlike the Steripen, you don’t need batteries to operate the LifeStraw.
  • Effective. The LifeStraw filters out most bacteria and parasites that cause travelers to become ill. 
  • Price. At the cost of around $20, the LifeStraw is excellent value for money. 


  • Purification is not 100%. While this is true, it will remove the vast majority of contaminants in the water, but some viruses and chemicals can get through.
  • Designed for single person use. The LifeStraw purifies water as you suck it into your mouth, limiting its use. You can’t use it to purify cooking water or share water with someone else. 


Like we said, going camping you’re will need a water purifier with modern purification technology. Luckily for you, we’ve already done the searching or you, and we made this little list of five outstanding water purifier pens. These things are affordable, efficient, and safe to use, and no adventurer should go without one. Now, the question is whether you like straws or pretty lights.

This article was last updated on December 5, 2022 .

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