Professional HVAC Tools,
Instant Results.
520+ free calculators for HVAC engineers, technicians, and homeowners. BTU load calculations, duct sizing, refrigerant charts, psychrometrics, energy ratings. All in one place. No login. No cost. Ever.
Browse All HVAC Tool Categories
Choose a category below to access specialized calculators, converters, and reference tools — all free, all instant.
Load Calculations
Heat load, cooling load, Manual J estimation, BTU calculators, room-by-room and whole-house analysis tools.
Duct Design & Airflow
Duct sizing, static pressure, CFM, velocity, leakage, equivalent diameter, and supply/return balancing tools.
Refrigeration
Refrigerant charge, superheat, subcooling, P-T charts, refrigerant comparison, oil separators, and leak tools.
Psychrometrics
Dew point, wet-bulb, enthalpy, humidity ratio, psychrometric chart, moisture content, and comfort zone calculators.
Ventilation & IAQ
Ventilation rates, air changes per hour, exhaust fan sizing, makeup air, CO₂ estimators, and ASHRAE 62.1 tools.
Energy Efficiency & Ratings
SEER, COP, EER, HSPF, AFUE calculators, energy savings estimators, carbon footprint, and payback period tools.
Unit Converters
Temperature, pressure, airflow, BTU/kW, length, area, volume, velocity, and mass flow unit conversions for HVAC.
Electrical for HVAC
Amperage, wire sizing, breaker sizing, power factor, voltage drop, MCA/MOP calculators, and electrical load tools.
Piping & Hydronic Systems
Pipe sizing, flow rate, pressure drop, pump sizing, GPM calculators, and hydronic heating system design tools.
Boiler & Heating Systems
Boiler output, radiator sizing, hot water heating loads, expansion tank sizing, and steam system calculators.
Indoor Air Quality
IAQ calculators, CO₂ estimators, filter efficiency, MERV rating guide, pollutant load, and fresh air requirement tools.
Solar & HVAC Integration
Solar heat gain, solar panel sizing for HVAC loads, net-zero calculations, and renewable energy HVAC tools.
Noise & Acoustics
NC rating calculators, sound attenuation, duct breakout noise, terminal unit sound power, and acoustic design tools.
Cost & ROI Estimators
HVAC installation cost, maintenance cost, ROI, payback period, service quote generator, and lifecycle cost analysis.
Troubleshooting Tools
Fault code lookup, diagnostic checklists, refrigerant leak estimator, system performance analysis, and fault isolation guides.
Compliance & Codes
ASHRAE 62.1, ASHRAE 90.1, NBC Canada, energy code compliance checkers, and building standard reference tools.
Commercial HVAC Tools
Chiller sizing, cooling tower, VAV box sizing, AHU design, commercial load calculations, and building automation tools.
Residential HVAC Tools
Home cooling/heating calculators, mini-split sizing, furnace sizing, heat pump selection, and residential energy audit tools.
Lab & Testing Tools
Air balancing, TAB calculators, duct leakage test, pressure test, performance verification, and commissioning tools.
Reporting & Generators
Service report generator, maintenance log, inspection checklist builder, load report, and printable HVAC documentation.
Most Popular HVAC Tools
Jump directly to the tools HVAC professionals use most every day.
Built for Real HVAC Work
Every tool on AskHVAC.ca is designed to the standard that HVAC professionals actually need — accurate, fast, and trustworthy.
Results appear the moment you click — no spinners, no waiting. Silent, real-time computation on your device.
All calculations follow ASHRAE standards, ACCA Manual J/D, CSA, and current industry codes. Verified by professionals.
Fully responsive on phone, tablet, and desktop. Use it on the job site from your phone — no app install needed.
Download results as PDF, CSV, or copy to clipboard. Print professional reports to share with clients or contractors.
Switch language instantly. Full RTL support for Arabic, Farsi, Urdu, and Hebrew. Serving HVAC professionals worldwide.
Every tool is 100% free. No account needed. Your calculation data stays on your device — never sent to any server.
Charts, graphs, and system diagrams render alongside your results — making it easy to present findings to clients.
WCAG 2.1 AA compliant. Full keyboard navigation, screen reader support, high-contrast mode, and reduced-motion options.
What HVAC Professionals Say
From residential technicians to commercial engineers — here is what the industry thinks of AskHVAC.ca.
"I use the duct sizing and BTU calculator every single day on the job site. Faster than any app I've paid for, and the results are spot on with my Manual J software."
"The psychrometric calculator alone is worth bookmarking this site. I've recommended AskHVAC.ca to my entire engineering team — it's become our go-to quick reference."
"Finally a free HVAC tool site that actually looks professional. Dark mode, export to PDF, works on my phone — this is what the industry needed. Bookmarked immediately."
Explore the Full HVAC Toolkit
Every tool on AskHVAC.ca links to related calculators, forming a seamless professional workflow from load analysis to final commissioning.
🌡 HVAC Load & Sizing
Accurate heat load calculations are the foundation of every HVAC project. Use our BTU calculator to determine heating and cooling requirements, then the cooling load calculator for summer peaks. The Manual J estimator follows ACCA protocols. Cross-reference with duct sizing and CFM calculators to balance airflow throughout the system.
❄ Refrigeration & Psychrometrics
Start with the refrigerant P-T chart, then verify system performance with the superheat and subcooling calculator. Check refrigerant charge with our charge calculator. For air-side analysis, the psychrometric calculator delivers enthalpy, dew point, wet-bulb temperature, and humidity ratio instantly.
⚡ Energy Efficiency & Compliance
Compare equipment using our SEER calculator, COP calculator, and EER calculator. Estimate viability with the payback period calculator. For code compliance, check ventilation via ASHRAE 62.1, envelope with ASHRAE 90.1, and Canadian projects against NBC Canada guidelines.
🔌 Electrical, Piping & Hydronic
Size conductors with our wire sizing calculator, breaker sizing calculator, and amperage calculator. For hydronic systems, use the pipe sizing calculator, pressure drop calculator, and pump sizing calculator. Boiler projects benefit from boiler output and expansion tank calculators.
🌧 Ventilation, IAQ & Air Quality
Determine fresh air requirements with our ventilation rate calculator and verify standards using the air changes per hour calculator. Assess indoor air quality with the CO₂ level estimator, choose filtration using our MERV rating guide, and size exhaust systems with the exhaust fan sizing tool.
💰 Cost Estimators & Converters
Present accurate budgets using our HVAC installation cost estimator and equipment ROI calculator. Our temperature converter, pressure converter, airflow converter, and BTU to kWh converter handle every HVAC unit instantly — with full Imperial and Metric toggle built in.