What HVACLoadCalc is for

Free BTU room chart — print it.

Room-by-room HVAC sizing for DIY mini-split installs.

Not ACCA Manual J. Oversizing is the #1 DIY mistake; we say so.

This map lists pages that exist. It is not a keyword dump and it does not treat every article as its own niche. The calculator (or the pack) is the hub. Guides sit under one pillar each.

Room BTU

25 BTU/sq ft in the calculator, then the four knobs.

• HVAC load calculator — Room BTU, mini-split, duct CFM, baseboard tabs.
• BTU room chart — Printable factor sheet for this calculator’s 25 BTU/hr baseline.
• BTU per square foot — The 25 BTU/hr baseline and the factors around it.

Mini-split heads

The calculator picks the smallest head at or above the room load.

• Mini-split by room — Head size vs real rooms.
• Mini-split BTU and SEER2 chart — ENERGY STAR single-zone rows, accessed October 6, 2026.
• ENERGY STAR room AC and dehumidifier sizing data

Whole-home size

A house is not one giant bedroom.

• AC for 1,000 sq ft — Worked small-house size.

Distribution

Air and electric heat after the load is known.

• Duct CFM chart — BTU ÷ (ΔT × 1.08).
• Baseboard watts — BTU/hr ÷ 3.41, not a watts-per-square-foot chart.

Questions

Sourced data

• What size air conditioner for a 12x12 room — The ENERGY STAR room AC size for a 12 by 12 room.
• What size air conditioner for a 10x10 room — 100 sq ft, the bottom of ENERGY STAR's smallest row, with each adjustment worked out.

Room air conditioner and dehumidifier sizes taken from the ENERGY STAR charts.

• What size air conditioner for a 150 sq ft room — 5,000 or 6,000 BTU/hr on the chart line.
• What size air conditioner for a 200 sq ft room — 6,000 BTU/hr inside the 150 up to 250 row.
• What size air conditioner for a 250 sq ft room — 6,000 or 7,000 BTU/hr on the chart line.
• What size air conditioner for a 300 sq ft room — 7,000 or 8,000 BTU/hr on the chart line.
• What size air conditioner for a 400 sq ft room — 9,000 or 10,000 BTU/hr on the chart line.
• What size air conditioner for a 500 sq ft room — 12,000 BTU/hr in the 450 up to 550 row.
• What size air conditioner for 600 sq ft — 14,000 BTU/hr in the 550 up to 700 row.
• What size air conditioner for 700 sq ft — 14,000 or 18,000 BTU/hr on the chart line.
• What size air conditioner for 800 sq ft — 18,000 BTU/hr in the 700 up to 1,000 row.
• What size air conditioner for 1,200 sq ft — 21,000 or 23,000 BTU/hr on the chart line.
• What size air conditioner for 1,500 sq ft — 24,000 or 30,000 BTU/hr on the chart line.
• What size air conditioner for 2,000 sq ft — 30,000 or 34,000 BTU/hr on the chart line.
• What size air conditioner for a kitchen — add 4,000 BTU/hr; a 150 up to 250 sq ft kitchen is 10,000 BTU/hr.
• What size dehumidifier for a basement — 20–30, 25–40, or 30–50 pints under 2,000 sq ft.
• What size dehumidifier for 2,000 sq ft — 30+, 40+, or 50+ pints, and better to oversize.

Guides

Pages that use DOE, ENERGY STAR, or EPA language and a worked pass through this calculator. Not a second topic map.

• What BTU stands for — British thermal units per hour, and 12,000 Btu in a ton.
• How an air conditioner works — heat leaves; oversizing cuts the cycle short.
• Portable air conditioner sizing — DOE SACC, not the window-unit chart.
• Clean the filter — airflow, not a new BTU target.
• Air conditioner efficiency — DOE steps, plus a shaded-versus-sunny calculator run.
• Dispose of an air conditioner — EPA refrigerant recovery before the unit is scrap.
• BTU to kW — 3,412 Btu/h per kW, and why that is not a furnace size by itself.
• How long air conditioners last — DOE life spans, and resize instead of copying the old nameplate.
• Heat pump sizing — heating load versus cooling load, before anyone orders equipment.

On your site

• Methodology — how the calculator works and how pages are written.
• Embed the calculator — an iframe, with the credit link kept.

Sisters

Running a central air conditioner on a backup generator is a wattage problem, not a BTU problem. That load belongs on GeneratorSizer.