These calculators provide preliminary estimates for qualified professionals only. They are not a substitute for analysis by a licensed engineer, some use region-specific assumptions, and you are responsible for verifying every result before use. Terms of Use

Calculators

Online tools for engineering calculations

Duct Sizing

Air velocity for round and rectangular ducts by flow rate Q, m³/h.

Psychrometric Calculator

All moist air parameters (φ, d, h, ρ, v, Tdp, Twb) with I–d chart.

Outdoor Unit Grille Sizing

Size intake & discharge grille area for a condenser in a niche, by capacity and free-area coefficient η.

Cooling Load Calculator

AC cooling capacity (TR, Btu/hr, kW) and required air flow by floor area, building type and load factors.

Pool Ventilation Calculator

Supply air flow for an indoor swimming pool hall by air-change rate, with fresh/recirculated split.