Best Water Purification Tablets

Updated August 2023
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Best of the Best
Potable Aqua Water Purification Treatment (50 Tablets)
Potable Aqua
Water Purification Treatment (50 Tablets)
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Effective In 35 Minutes
Bottom Line

These can go to work and purify in roughly 35 minutes.


This product is very easy to use, just drop 2 tablets into a quart. Wait 5 minutes, shake, and wait 30 minutes more. When used as directed, it is effective against Giardia lamblia, a microscopic parasite that causes diarrhea.


Ingredients may leave an unpleasant taste, which can be hard for some individuals to swallow.

Best Bang for the Buck
Aquatabs World's Best Water Purification Tablets
World's Best Water Purification Tablets
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Sizable Package
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Comes with a large quantity, making it a great choice for travelers or camping.


Composed of high-quality ingredients to purify in just half an hour. Stays effective for 5 years, making it a great long-term option. Sizable option remains small enough to fit into backpacks or purses. Remains tasteless and odorless.


Smaller than other products on our list.

Potable Aqua Chlorine Dioxide Water Purification Tablets
Potable Aqua
Chlorine Dioxide Water Purification Tablets
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For Outdoor Enthusiasts
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A product that provides greater protection than many others on the market.


The active ingredient is effective against bacteria and viruses and is the only EPA-approved active ingredient that is effective on cryptosporidium cysts, which can cause respiratory and gastrointestinal illness. Can treat one quart of water, and is good for campers and hikers as well as international travelers.


This product takes 4 hours to become fully effective, so you will need to plan ahead before using.

Coghlan's Drinking Water Tablets
Drinking Water Tablets
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Simple Yet Solid
Bottom Line

This is a reliable product that ensures safety and clean H2O.


Pack of 50 can be used for small camping trips, hiking, emergency kits, and more based on the user's preferences. Protects against most bacteria, including Giardia. Lightweight, so simple to carry around during outdoor activities.


May not be as effective as other types of products on this list.

Katadyn Micropur Purification Tablets
Micropur Purification Tablets
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Expert Recommended
Bottom Line

Designed for heavy-duty operation, these work best for emergency situations.


Registered with the EPA as a microbiological purifier. Simply drop in the tablet—no need for mixing or measuring. Protects against most major bacteria and viruses. Works with most major sources, including rainwater, lakes, and rivers.


Expiration date can be confusing, so make sure to check it.


We recommend these products based on an intensive research process that's designed to cut through the noise and find the top products in this space. Guided by experts, we spend hours looking into the factors that matter, to bring you these selections.

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Buying guide for best water purification tablets

You have probably heard the expression, "Water, water everywhere, and not a drop to drink." When hiking or camping, this saying too often applies. There may be a stream, lake, or spring accessible, but the water may contain pathogens, germs, bacteria, gunk, and tadpoles. You are afraid to drink the stuff, yet you are desperately thirsty.

Whether you’re thirsty in the wilderness, in a location where water purity is questionable, or during a natural disaster when snowmelt, floods, or heavy rains may have contaminated your water, there is a solution: water purification tablets. These tablets provide a safe solution so you can have potable water.

Read on to learn about the uses and benefits of water purification tablets. We’ll discuss their importance in your home’s shelter-in-place survival kit as well as your hiking or camping pack. When you are ready to make a purchase, we invite you to consider our top recommendations.

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When packing your gear for an outdoor adventure, whether it’s hiking, fishing, camping, or rock climbing, don’t forget to include your water bottle, water purification tablets, and a container for harvesting rainwater or scooping water from the creek, lake, or river.

Benefits of water purification tablets

Convenience and safety

Convenience is a huge benefit of water purification tablets. You can easily carry them with you in a purse, briefcase, or backpack for those times when you need purified water. But the biggest benefit these tablets offer is safety. With water purification tablets, you can make sure your water is safe to drink when the source of the water is questionable.

In addition to convenience and safety, you will find that water purification tablets are quite economical. The price isn’t exorbitant, and the money you spend on the tablets would surely be less than the money you’d spend on a trip to the emergency room.

During a disaster

During an emergency, when water is required for survival, you need clean water to drink. Humans may be able to survive up to three weeks without food, but it is impossible for the human body to survive more than 100 hours without hydration. In an emergency scenario, having water purification tablets available can help you survive past the 100-hour mark — until emergency help arrives.

In the military

Water purification tablets are a product of military necessity. When war broke out in Europe during World War II, the U.S. government issued Halazone tablets, a chlorine-based water purification tablet used for the disinfection of contaminated water, to be included in the survival packs of all military personnel.

Today, new formulations of water purification tablets or drops with a long shelf-life can provide safe drinking water for armed forces deployed around the globe.

Humanitarian aid applications

During a flood or other disaster, while humanitarian workers attempt to repair or provide a source of fresh water, water purification tablets may be dispensed to provide an immediate source of potable water for persons at risk.

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For your safety
Don’t drink water immediately after adding water purification tablets. To prevent infection from difficult-to-eradicate organisms, it is best to wait 45 minutes or more to allow the purification chemicals time to work. Check the instructions.

Types of water purification tablets

Chlorine dioxide

Undoubtedly the best and most effective water purification tablet formula contains chlorine dioxide. With no horrid taste or noxious smell, there is little chance of nausea. There are fewer potential side effects than there are with chlorine or iodine tablets. Chlorine dioxide eliminates a wide variety of viruses, germs, and bacteria, including cryptosporidium and giardia lamblia, commonly known as “beaver fever.”

Chlorine (sodium dichloroisocyanurate)

Chlorination, or the process of using chlorine to purify water, became a common practice over a century ago. Chlorine effectively destroys viruses and bacteria that cause typhoid, cholera, gastroenteritis, and dysentery. Chlorine, combined with effervescent salts such as adipic acid and sodium bicarbonate in a rapidly dissolving tablet, is an effective method of water purification for use when potable water is inaccessible. However, chlorination is not an effective method of eliminating cryptosporidium.

To purify water with chlorine tablets, follow the manufacturer’s package directions, allowing the water to “rest” for 45 minutes before use. Water treated with chlorine may taste and smell like bleach. The scent and taste will dissipate if the water is allowed to sit uncovered overnight. The shelf life of chlorine-based water purification tablets is three to five years.

Iodine (tetraglycine hydroperiodide)

When most of us think of iodine, we either think of the iodine in processed table salt or the brown stinging liquid our grandparents used to prevent infection in cuts and scrapes. Iodine water purification tablets are a compound specifically formulated to effectively eradicate microorganisms such as parasites, bacteria, and viruses that may be present in impure water.

When using iodine water purification tablets, follow the manufacturer’s package directions, allowing the water to sit for a minimum of 30 minutes after the tablets have been added.

  • Keep in mind when using iodine water purification tablets that cold water takes longer to purify than water that is room temperature.

  • The quality of the water affects the amount of iodine required to purify the liquid to a safe and palatable degree. Cloudy or murky water may require more tablets. If you see particles in the water, filter it before consumption.

Iodine water purification tablets are effective against common viruses and bacteria such as salmonella, cholera, and E. coli. However, water must sit for at least 45 minutes at 75°F or warmer to completely guarantee purification. After sitting for an hour, iodine has proven effective at eliminating giardia but provides no protection against cryptosporidium.

Potential buyers may note that water purified with iodine can have a bad aftertaste. However, there are more tablets or pills to remove the taste of iodine from the treated water once the iodine has completely purified the liquid.

The majority of people find iodine-treated water to be safe with no side effects. Unfortunately, persons reactive to iodine may experience headaches, nausea, muscle cramps, and a persistent metallic taste in their mouth. The average shelf life of most iodine-based water purification tablets is five to seven years.


Water purification tablets are relatively inexpensive, convenient, and easy to use. Most tablets are packaged in small bottles that can be easily carried transported. They are used the same way: drop tablets into the appropriate amount of water and wait for the period of time specified in the instructions. Stored dry in an airtight container, the tablets can last up to five years.

Water purification tablets are typically sold in packages of 30, 60, and 120 tablets.

Water purification tablet prices

When choosing water purification tablets, consider which brand offers the best efficiency against pathogens, how long the tablets take to work, and the different types of chemicals they contain. The price of water purification tablets depends on the ingredients, the brand, and the product shelf life.

In the lower price range, water purification tablets cost from $3 to $7 for 120 tablets. The brands that make these tablets may be less recognizable. In the medium-price range, you’d pay $8 to $10 for the same quantity of tablets, but they are more likely to come from a brand with an established reputation.

Chlorine dioxide tablets typically cost more than chlorine-based and iodine-based water purification tablets. You can expect to pay from $10 to $18 for a packet of 30 tablets, which is a considerable price hike (yet still a reasonable cost).


  • Keep water purification tablets out of the reach of children and pets. Like medication in tablet form, water purification tablets may look like candy.

  • When preparing a family disaster kit, be sure to provide enough water purification tablets to take care of the needs of pets as well as family members.

  • Pack a clean water bottle with your water purification tablets.

  • When shopping for water purification tablets, look for tablets with ingredients approved by the U.S. Environmental Protection Agency (EPA).

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In an emergency, harvest available water, drop in water purification tablets, and allow the water to sit before drinking. These simple steps can prevent dehydration without the risk of ingesting waterborne pathogens.


Q. Is it safe to use water purification tablets in the water I use as drinking water for my pets?

A. Be cautious here. Although the answer may be “yes,” if your pet has allergies or sensitivities to iodine or chlorine — or if you have any other doubts — be sure to check with your veterinarian first.

Q. What is the most common water-borne illness?

A. The EPA advises that each year, more than 200 million people are infected with giardiasis. It is the most widespread intestinal protozoan infection worldwide.

Q. How many people in the U.S. are infected with giardiasis annually?

A. In the U.S., approximately 1.2 million people are infected each year. In some instances, these infections could have been prevented with the use of water purification tablets.

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