How many BTU for 500 square feet?
500 sq ft × 25 BTU = 12,500 BTU baseline. With average insulation, round up to a 12,000 or 18,000 BTU unit depending on sun and ceiling height.
What Size AC Do I Need?
Living rooms and open areas need more BTU per square foot than bedrooms — more windows, people, and electronics. Enter your space and toggle kitchen load if cooking appliances share the zone.
Space dimensions
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Sizing settings
Open floor plans and single-zone limits
One mini-split head can cool an open kitchen-living-dining area if airflow reaches all corners. Hallways and closed bedrooms off that zone may stay warm — our open floor plan sizing guide covers when one head is enough.
500 sq ft × 25 BTU = 12,500 BTU baseline — round up to 12,000 or 18,000 BTU depending on sun and ceiling height.
Occupants and kitchen load
Each person beyond the first two adds sensible heat. A range or oven running during dinner adds spike load — enable kitchen load in settings for combined kitchen-living spaces.
Frequently asked questions
Do people affect AC sizing?
Yes. Each person adds roughly 600 BTU of sensible heat beyond the first two occupants. Enter occupant count in project settings.
Should I size for the hottest day of the year?
Size for design conditions in your climate — not record heat waves. In hot-humid zones, consider upsizing one step or improving insulation instead.
Related calculators
HVAC Calculators · https://hvaccalculators.net/what-size-ac-do-i-need/