What Size Air Conditioner Do I Need?
A quick reference for what size air conditioner fits common room sizes, and the factors that push the right size up or down.
For a room with typical sun exposure and two or fewer occupants, room size alone gets you most of the way to the right AC size.
Quick reference by room size
| Room size | Recommended BTU/hr |
|---|---|
| 150 sq ft (small bedroom) | 5,000-6,000 |
| 300 sq ft (bedroom or office) | 7,000 |
| 500 sq ft (living room) | 10,000-12,000 |
| 1,000 sq ft (open floor plan) | 18,000 |
What pushes the number up
- A room that gets direct sun for much of the day.
- More than two people regularly using the room.
- A kitchen, or any room with heat-generating appliances.
- High ceilings, which add volume beyond what floor area alone captures.
Enter your room's actual conditions into the BTU Calculator for a number specific to your space instead of a generic range.