Unlike window ACs, portable air conditioners roll easily from room to room and are quick to set up, with no labor-intensive mounting and very few tools. Most just require a nearby window and wall outlet to get cold air flowing. While they're a bit more expensive, you can't beat the convenience—plus your view isn't blocked by a metal box and you can open and close your window whenever you please.

Portable air conditioners have a internal fan that moves hot, humid air over a refrigerant gas-filled coil to cool and expel it into a room to lower the temperature. The moisture vapor that's collected during this process drips into a pan for easy dumping. Higher-end units feature a condensation pump to draw water outside or to siphon it to a drainage system.

To find the best portable air conditioners to recommend, we tested units from trusted brands like LG, Black + Decker, Midea, and more. These are the units that stood out and are worth the investment.

Manufacturers provide the number of square feet a given unit can cool, assuming average ceiling height. If the room is especially hot in the summer (it’s in an attic or has large, south-facing windows) we recommend moving up to the next size. Air conditioners’ cooling capacity is typically measured in British Thermal Units, or BTU, per hour. To gauge coverage, figure roughly 20 BTU per square foot of space. Most portable AC units range from 5,000 and 20,000 BTUs.