Free Professional Home Calculators
Every calculator in our library is built on verified industry standards — from ACCA Manual J for HVAC load sizing to IRC building codes for construction waste logic and SEER2 efficiency ratings for energy analysis.
Whether you need to size a new air conditioner for a 2,500 sq ft home, estimate how many bags of concrete a footing pour requires, or calculate your debt-to-income ratio before applying for a mortgage, HomeCalc Pro gives you contractor-grade precision in a free, no sign-up tool. Use the category filters below to find exactly what you need across our 100+ calculators spanning HVAC & Heating/Cooling, Construction Materials, Home Improvement, Landscaping & Outdoor, Energy & Utilities, Mortgage & Finance, and Real Estate & Property.
Explore Our Free Calculator Library
Professional-grade estimation tools at your fingertips. Browse by category or use the search below to find the exact calculator for your home project.
HVAC & Energy
HVAC Load Calculator
Free Manual J load calculation. Get accurate BTU requirements for your home to choose the right size furnace and AC system. Avoid costly mistakes.
AC Size (BTU) Calculator
Find the perfect air conditioner size. Our BTU calculator helps you determine the right cooling capacity for any room based on size and conditions.
Duct Size Calculator
A free HVAC duct sizing calculator to determine the proper duct diameter for your system based on airflow (CFM). Ensure optimal performance.
SEER Savings Calculator
Estimate your annual savings by upgrading to a high-efficiency AC unit. See your potential cost reduction and payback period with a new SEER2 system.
Mini-Split Cost Estimator
Get a budget estimate for a new ductless mini-split system. Find the installed cost for a single-zone or multi-zone setup for your home.
Furnace Cost Estimator
Planning a furnace replacement? Get an estimated cost for a new gas, electric, or oil furnace installation based on your home size and climate.
Heat Pump Cost Estimator
Estimate the total installed cost of a new heat pump. Compare prices based on unit size and efficiency (SEER2) to budget for your project.
Thermostat Savings Calculator
See how much you can save on your energy bill. Calculate annual savings from using a programmable or smart thermostat with temperature setbacks.
Attic Insulation Calculator
Find out how many bags of blown-in insulation you need. Calculate the material required to reach your attic's recommended R-value for your zone.
Ventilation Fan CFM Calculator
Calculate the right CFM for your exhaust fan. Ensure proper bathroom or kitchen ventilation with our airflow capacity and fan sizing tool.
Dehumidifier Size Calculator
Find the right dehumidifier size for your basement or room. Calculate the correct pint capacity based on room size and moisture level.