BTU Load Calculator
Estimate room heating and cooling BTU load from area, ceiling height, insulation, and sun exposure for faster...
Open calculatorFree HVAC, Plumbing & Electrical Calculators
Get fast, practical estimates for field planning and homeowner projects. Built for contractors, technicians, estimators, and DIY users who need clear numbers quickly.
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HVAC Featured Calculators
Popular HVAC sizing and airflow estimates for quick planning in the field.
AC Tonnage Calculator
Convert conditioned area and insulation assumptions into estimated BTU demand and AC tonnage to shortlist prac...
Open calculatorCFM Airflow Calculator
Calculate required airflow CFM from room dimensions and target ACH so HVAC teams can estimate ventilation and...
Open calculatorPlumbing Featured Calculators
Frequently used plumbing estimators for water heating, pipe planning, and drainage runs.
Water Heater Size Calculator
Estimate recommended storage water heater gallons from occupants, bathrooms, and simultaneous hot-water demand...
Open calculatorPipe Size Calculator
Estimate nominal supply pipe size from fixture count, run length, and material assumptions to support quick pl...
Open calculatorDrain Slope Calculator
Calculate total vertical drop for drain runs from slope per foot so plumbing crews can set elevations quickly...
Open calculatorElectrical Featured Calculators
High-use electrical calculators for fast load, drop, and breaker planning checks.
Watts Amps Volts Calculator
Calculate watts, amps, or volts by entering any two known electrical values for fast field checks and planning...
Open calculatorVoltage Drop Calculator
Estimate voltage drop across conductor runs for early branch and feeder planning.
Open calculatorBreaker Size Calculator
Estimate breaker sizing from connected load assumptions and basic continuous-load planning factors.
Open calculatorPopular Tasks
How It Works
1
Enter job details
Fill in room, airflow, fixture, slope, or electrical load inputs using practical field assumptions.
2
Get an estimate
Review calculated outputs instantly with practical planning ranges.
3
Share or print results
Use querystring links to share results and print a clean summary for job records.
Built for the field: quick assumptions, clear outputs, and links to related HVAC, plumbing, and electrical calculators.