CalculateGuideCalculateGuide
  • Electrical
    • All Electrical
    • DC/AC Circuits
    • Cable & Protection
    • AC & Three Phase
    • Electronics
    • Motors & Machines
  • Mechanical
    • All Mechanical
    • Fluids
    • Rotation
    • Machinery
    • Force & Motion
  • Construction
    • All Construction
    • Concrete
    • Rebar & Steel
    • Materials Estimating
    • Surveying
    • Structural
  • HVAC
    • All HVAC
    • Cooling & Heating
    • Ventilation
    • Plumbing
  • Physics
    • All Physics
    • Energy
    • Motion & Force
  • Metal & Steel
    • All Metal & Steel
    • Weight
    • Dimensions
  • Architecture
    • All Architecture
    • Floor & Wall
    • Rooms & Spaces
    • Lighting Design
  • More
    • Logistics
    • Finance
    • Math
    • Automotive
    • Solar
  • About Us
  • Guides
  • EN|DE
    • All Electrical
    • DC/AC Circuits
    • Cable & Protection
    • AC & Three Phase
    • Electronics
    • Motors & Machines
    • All Mechanical
    • Fluids
    • Rotation
    • Machinery
    • Force & Motion
    • All Construction
    • Concrete
    • Rebar & Steel
    • Materials Estimating
    • Surveying
    • Structural
    • All HVAC
    • Cooling & Heating
    • Ventilation
    • Plumbing
    • All Physics
    • Energy
    • Motion & Force
    • All Metal & Steel
    • Weight
    • Dimensions
    • All Architecture
    • Floor & Wall
    • Rooms & Spaces
    • Lighting Design
    • All Logistics
    • Shipping
    • Inventory
    • All Finance
    • Loans & Credit
    • Investment
    • Business & Pricing
    • All Math
    • Percentages
    • Geometry
    • Algebra
    • Basic Math
    • Statistics & Probability
    • All Automotive
    • Performance
    • Cost & Usage
    • Tires & Wheels
    • All Solar
    • Solar
    • Energy Economics
  • About Us
  • Guides
  • EN|DE
Skip to content
Free Online Calculators
  • Free Online Calculators
  • About Us
Home / HVAC

HVAC Calculators

Free HVAC calculators for BTU, AC tonnage, sensible and latent heat, heat pump size, hydronic flow rate, airflow, duct size and elbow pressure drop, refrigerant line sizing, superheat and subcooling, wet bulb, and humidity. 22 calculators across 3 categories.

Cooling & Heating

BTU CalculatorOpen →Dew Point CalculatorOpen →Delta T CalculatorOpen →Heat Load CalculatorOpen →AC Tonnage CalculatorOpen →Furnace Size CalculatorOpen →Humidity CalculatorOpen →R-Value CalculatorOpen →Heat Index CalculatorOpen →Superheat and Subcooling CalculatorOpen →Wet Bulb CalculatorOpen →Refrigerant Pipe Size CalculatorOpen →HVAC Sensible Heat CalculatorOpen →Heat Pump Size CalculatorOpen →Hydronic Flow Rate CalculatorOpen →

Ventilation

CFM CalculatorOpen →Air Changes Per Hour CalculatorOpen →Duct Size CalculatorOpen →Fan Power CalculatorOpen →Duct Elbow Pressure Drop CalculatorOpen →

Plumbing

Water Heater Size CalculatorOpen →Expansion Tank CalculatorOpen →
© 2026 Free Online Calculators • Built with GeneratePress
Free Online CalculatorsFree Online Calculators

Free online calculators and calculation tools for engineering, trades, and everyday math. Fast, accurate, and always free.

© 2026 Free Online Calculators. All rights reserved.