Electrical Calculators
Work through common electrical and heating relationships with calculators for electricity use, voltage drop, resistance, Ohm’s law, and BTU sizing. Enter the quantities and units requested by each tool to estimate a result from the stated equation, then review the cited guidance and safety limitations before applying it to real equipment.
What can you calculate here?
Choose a focused tool below for a transparent, shareable result backed by the method and sources shown on its page.
BTU Calculator
BTU Calculator estimates heating capacity from floor area and BTU per square foot.
Electricity Calculator
Electricity Calculator estimates energy cost from kilowatt-hours and the entered electricity rate.
Voltage Drop Calculator
Voltage Drop Calculator returns circuit voltage loss from entered current and total resistance.
Resistor Calculator
Resistor Calculator returns circuit resistance from entered voltage and current using Ohm’s law.
Ohm's Law Calculator
Ohm's Law Calculator returns circuit voltage from entered electrical current and resistance.