Know your room size? Start here.

Find your mini-split BTU range

Enter what you know about the room. We’ll estimate a single-zone size and show real models in that capacity class.

This is a useful starting point, not a Manual J load calculation. Confirm final sizing with an installer.

Tell us about the room

Most homes are 8–10 ft. Half-foot entries are fine.

ZIP lookup uses a representative static HUD-USPS ZIP-to-county plus PNNL county-to-IECC crosswalk. If your ZIP is not in the static set, choose the IECC zone directly.

Your starting point

12k BTU

9k BTU - 12k BTU estimated range

Example: 500 sq. ft., 8 ft. ceiling, Denver IECC zone 5B, average insulation, typical sun, living room.

A few real models in this size:

See the 12k BTU capacity guide

Static sizing table

This table renders without JavaScript and comes from the ENERGY STAR room air conditioner sizing chart.

Area to be cooledCapacity neededMatching capacity class on this site
100 to 150 sq. ft.5,000 BTU/hr9k BTU
150 to 250 sq. ft.6,000 BTU/hr9k BTU
250 to 300 sq. ft.7,000 BTU/hr9k BTU
300 to 350 sq. ft.8,000 BTU/hr9k BTU
350 to 400 sq. ft.9,000 BTU/hr9k BTU
400 to 450 sq. ft.10,000 BTU/hr12k BTU
450 to 550 sq. ft.12,000 BTU/hr12k BTU
550 to 700 sq. ft.14,000 BTU/hr18k BTU
700 to 1000 sq. ft.18,000 BTU/hr18k BTU
1000 to 1200 sq. ft.21,000 BTU/hr24k BTU
1200 to 1400 sq. ft.23,000 BTU/hr24k BTU
1400 to 1500 sq. ft.24,000 BTU/hr24k BTU
1500 to 2000 sq. ft.30,000 BTU/hr36k BTU
2000 to 2500 sq. ft.34,000 BTU/hr36k BTU

Sources behind this calculator