We may receive a commission on purchases made from links.

The 'Self-Cleaning' Water Bottle, Explained

Your water bottle shouldn't be stinky. Some fancy new products want to help.

Having a reusable water bottle is one of the best ways to remind yourself to stay hydrated all day. Its presence will remind you to periodically pop the cap off and take a big swig. But as neutral a vessel as a water bottle might seem—after all, it's just water, right?—you're probably not washing it as often as you should be, and after a while, you might notice a funny mildew smell emanating from it, or a film forming across the interior.

New bottles have begun to hit the market that claim to be self-sanitizing, and while they're not cheap, the selling point is that you won't need to remember the last time you rinsed them out with soap and water. Let's look into this new frontier of water bottle tech.

How does a self-cleaning water bottle work?

A self-cleaning water bottle theoretically works by way of an interior ultraviolet light, usually located in the bottom of the cap. The process of using UV light to kill microorganisms is known as ultraviolet germicidal irradiation; as Insider explains, the UV rays damage the molecular bonds of the DNA in bacteria and viral particles, rendering their functions useless.


That being said, the self-cleaning function in these bottles isn't designed to remove things such as heavy metals and other non-biological contaminants found in water. So if you're going to shell out for this fancy-ass tech, it probably only makes sense for domestic use (home, office, gym) where you have access to treated water and not, say, the type of water you're exposed to while you're out camping or something.

There are now multiple brands producing self-cleaning water bottles, including LARQ ("water purification for the digital age"), Kiyo (by a company called Monos), and CrazyCap (who comes up with these names?). The offerings vary in terms of water bottle volume, how long it takes to self-clean, how often you have to recharge the cap, and the relative intensity of the cleaning.


How often should we be cleaning reusable water bottles?

Not everyone's going to want to drop something like $50-$100 on a high-tech water bottle, so the real question is, how often should you be washing any of your normal water bottles? According to experts, ideally you should be washing your reusable bottle daily, and sanitizing it more thoroughly at least once a week. A bottle brush like this makes the job easier.


Wait. Have I been living in squalor this entire time? Don't answer that. I guess if you consider daily/weekly washings too much to keep track of, dropping $100 to stay hydrated and virus-free might be worth it to you. For now, I'll stick to my trusty office cup, but I think I'll do myself a favor and stick it in the dishwasher a little more often.