Buy at AmazonIf you drink a lot of canned beverages like beer or seltzer, a stainless-steel koozie might be worth adding to your collection to keep your drink cold for as long as possible. Our winner, the Igloo Coolmate, excelled at insulating our drinks. It was straightforward to use, comfortable to hold, and kept our canned drinks stable and secure.
Koozies, also known as cozies, stubby holders (in Australia), beer jackets, or can coolers, are sleeves that hold a canned beverage. They are primarily used to help insulate your drink and keep it cold, but they also shield your hand from condensation and make the can more stable when it’s sitting on a surface. Their ability to keep beverages cold make them popular with outdoorsy folks, especially for camping or sipping beachside.
Koozies typically come in two styles. Neoprene or foam koozies have been around for ages. Commonly used in wetsuits, neoprene is a foamed rubber containing microscopic pockets of nitrogen gas. Neoprene koozies are supremely affordable and lightweight, but maybe they aren’t the best choice if your priority is keeping your can cold for longer periods of time.
Over the last few years, we’ve noticed more brands making vacuum-insulated stainless-steel versions, which are heftier and more expensive, and they promise to keep drinks colder for longer. Neoprene and vacuum-insulated products work the same way: They isolate the cold can from air currents that would allow it to exchange heat with its surroundings, explained our senior science research editor, Paul Adams. Vacuum-insulated koozies are more effective because they contain fewer particles that can conduct heat, Adams said. Those are the products we focused on for this testing, plus a generic neoprene version for comparison.
Do Koozies Actually Keep Drinks Cooler?
We wanted to see if spending a bit more on stainless steel gets you better cold retention. In order to find out, we put a cold can of seltzer in each koozie and tracked the temperature until it exceeded 50 degrees, in a 72-degree room. The seltzer in the neoprene koozie warmed to more than 50 degrees in a little over an hour, a long time for one drink, but compared to the stainless-steel models, not long at all.
The least effective steel koozie kept a can of seltzer below 50 degrees for an average of 2½ hours. The best kept cans chilled for an average of 3¼ hours. A really long time for one drink, but remember, we were testing at room temperature; these times would be shorter under the hot sun, like at a beach, perhaps. We consider our winner’s capabilities to be promising for performance on hot days. Here are a few things to consider when looking for a koozie.
What to Look for
- Stainless-Steel and Vacuum-Insulated: We examined the wall thickness of each koozie and saw some trends that suggested thicker was better, but ultimately just choosing from vacuum-insulated stainless-steel koozies will get you most of the way there; these kept drinks cold much more effectively than the neoprene version.
- Easy Screw-On Gasket: Many koozies had separate gaskets that are meant to be screwed or pressed on to the can after inserting it into the cup in order to help keep it in place. These gaskets also help insulate the sides of the can and shield them from airflow. We preferred gaskets that screwed on seamlessly, with little additional effort.
Some koozies had separate gaskets that help insulate the can and keep it in place. We liked ones that screwed on seamlessly, with little additional effort.
Nice to Have
- Rubberized Base: We especially liked koozies that had a rubberized base. It not only made the koozie feel more stable when placed on a table but also made it quieter to set down on the counter, minimizing loud clanging.
What to Avoid
- Press-On Gasket: While many koozies had gaskets to help secure a can in place inside the metal cup, some were easier to use than others. Some gaskets had to be pressed down (or pressed and screwed). Because these were made of rubbery materials, they didn’t press down smoothly and caught on the surface of the can, so it took extra time to get them all the way on. It also made it more difficult to remove them.
Some gaskets had to be pressed down. They were made of rubbery materials, so they caught on the surface of the can, and it took extra time to get them on and off.
The Tests
- Insert cold cans of seltzer into each koozie and monitor seltzer temperature with thermometer, noting time it took for temperature to rise above 50 degrees Fahrenheit
- Insert cans of seltzer into koozie, then sip from the cans and walk around while holding them, noting ease of use
- Drop full and empty koozies from a height of 6 feet onto concrete, noting any damage
- Wash five times according to manufacturers’ instructions
- Recruit additional testers to try koozies and record their thoughts
How We Rated
- Performance: We measured how effective the koozies were at keeping beverages cold.
- Ease of Use: We evaluated how easy it was to insert cans into the koozies, drink from the cans, and clean the koozies. We also noted how comfortable the koozies were to hold.
