Electrical

Estimate the BTU/hr cooling and heating capacity a room or house needs, based on area, ceiling height, insulation, sun, climate and occupancy.

Estimate the daily, monthly and yearly cost of any appliance from its power rating in watts, run time and your per-unit electricity rate, plus a carbon footprint estimate.

Solve Ohm's law and Joule's law from any two known values: voltage, current, resistance or power, each in SI units with one click.

Decode a four-band resistor from its colour code: nominal resistance, tolerance and the minimum and maximum value range, with a logarithmic scale gauge.

Find voltage drop over a wire run from voltage, current, length, AWG gauge and conductor material, with drop percent and load voltage.