Ohm's law ties together the four core quantities of a simple electrical circuit: voltage in volts, current in amperes, resistance in ohms and power in watts. Enter any two of these values and this calculator solves for the remaining two using the standard relationships V equals I times R and P equals V times I. It is the everyday tool of electronics hobbyists, students and technicians who need to size a resistor, check a current draw, or work out how much heat a component will dissipate. Because the four quantities are all linked, knowing just two of them fully describes the circuit. Type your known values, press calculate, and read off the results. Everything runs locally in your browser, so it is instant and completely private.
Ohm's law states voltage equals current times resistance, written V=IR. This calculator also uses the power relations P=VI, P=I squared times R, and P=V squared over R.
Enter any two of voltage, current, resistance, or power. The calculator solves for the remaining two values automatically.
Voltage is in volts, current in amperes, resistance in ohms, and power in watts. Keep all inputs in base SI units for a correct result.
Ohm's law ties together the four core quantities of a simple electrical circuit: voltage in volts, current in amperes, resistance in ohms and power in watts. Enter any two of these values and this calculator solves for the remaining two using the standard relationships V equals I times R and P equals V times I.
Yes. Ohm's Law Calculator is completely free, with no sign-up and no usage limits.
Yes. Ohm's Law Calculator runs in any modern web browser. There is nothing to download or install.
Yes. Ohm's Law Calculator runs entirely on your device in your browser, so nothing you enter is uploaded to a server.