Dry ice in a cooler works great — pack it right.

Yes, you can absolutely use dry ice in a cooler. It stays cold way longer than regular ice and won’t make everything soggy. But you have to handle it carefully because it’s not regular ice.

Dry ice is solid CO₂, and it sublimates (turns into gas) instead of melting. That gas can build up in a sealed cooler and pop the lid off, or worse. So you need ventilation. Never seal the cooler airtight. Most coolers have a drain plug — leave it open or crack the lid a little. I put a piece of tape on the latch so nobody closes it all the way.

Pack the dry ice at the bottom, then a layer of cardboard or newspaper, then your food. The cardboard keeps food from freezing directly on the dry ice (it’ll freeze solid in minutes). For drinks, put them above the cardboard too, unless you want frozen cans that might burst.

Also: handle dry ice with insulated gloves. It’ll burn your skin. And don’t store it in your car’s trunk with the windows up. Keep the trunk cracked if you’re driving far.

One extra thing: dry ice evaporates about 5-10 pounds per 24 hours in a decent cooler. Plan accordingly. Future you will appreciate not dealing with wet, smelly melted ice.