Free MEP Calculators

43 calculators for HVAC, electrical, plumbing and civil design. Every result shows its formula and method, works in SI or IP units, and makes a PDF report.

23 calculatorsHVAC

Cooling load, air distribution, psychrometrics and chilled water systems.

Cooling Load
Duct Sizer
Duct ESP
CHW Pump Head
Fan Sizing

Open HVAC calculators →10 calculatorsElectrical

Loads, cables, protection, standby power and solar.

Breaker & Cable Sizing
Cable Voltage Drop
Generator Set Sizing
UPS & Battery Backup
Solar Rooftop PV

Open Electrical calculators →6 calculatorsPlumbing

Water supply pipes, water heaters and storage tanks.

Water Supply Pipe Sizer
Water Heater Sizing
Domestic Water Tank
Fire Water Tank

Open Plumbing calculators →4 calculatorsCivil

Site quantities for reinforcement, concrete and finishes.

Bar Bending Schedule
Concrete Quantities
Site Materials
Finishes Quantities

Open Civil calculators →

Results are for preliminary design and engineering review. Verify final selections against project specifications, applicable codes and manufacturer data.

Also on your phone: J1 Pro on Google Play – works offline and shares PDF reports.