BTU Calculator
Calculate the BTUs needed to heat or cool any room. Accounts for room size, ceilings, windows, climate zone, and occupants.
↳ 250 sq ft · hot climate → 8,750 BTU
HVAC Load Calculator
Whole-home simplified Manual J estimate. Enter square footage, insulation, climate zone, and window ratio to get cooling and heating loads.
↳ 2,000 sq ft · mixed climate → 3.5 tons
AC Size Calculator
Quick square footage to AC size lookup. Enter your floor area and climate, get a BTU and tonnage recommendation with a reference table.
↳ 1,200 sq ft · moderate → 2 ton unit
Furnace Size Calculator
Find the right furnace BTU output for your home. Includes climate zone, insulation quality, and efficiency (80% vs. 96% AFUE) recommendations.
↳ 1,800 sq ft · cold zone → 90,000 BTU
CFM / Airflow Calculator
Determine the airflow in cubic feet per minute required for a space. Set your room dimensions and air changes per hour target.
↳ 400 cu ft · 6 ACH → 40 CFM needed
SEER Savings Calculator
Estimate annual energy savings when upgrading to a higher SEER system. See payback period and lifetime CO₂ reduction.
↳ SEER 10 → SEER 18 · 3 tons → $380/yr saved