Ohm's Law Calculator

Enter any two known values to calculate voltage, current, resistance and power.

Ohm's law formulas

The main relationship is V = I × R. Electrical power is calculated using P = V × I.

The solver also supports power and resistance as the two known values, calculating current and voltage using their square-root relationships.

Apply these fundamentals alongside the wiki guidance on cabling and wiring rules, fire alarm earth-fault finding and monitored input resistor circuits.