Category hub
Weather Calculators
Browse 4 tools, including BTU Calculator, Wind Chill Calculator, Heat Index Calculator.
BTU Calculator
Estimate room-air-conditioner capacity using the ENERGY STAR area chart.
Wind Chill Calculator
Calculate the NWS wind-chill temperature within its cold, windy operating range.
Heat Index Calculator
Estimate shaded apparent temperature using the NWS heat-index algorithm.
Dew Point Calculator
Estimate dew point from air temperature and relative humidity using the Bolton saturation-vapor-pressure fit.
4 working tools. Each page explains its inputs, formula and assumptions.