TheCircuitDogCircuit Fundamentals
Ohm's Law Calculator
Use Ohm’s law to solve voltage, current, resistance or electrical power in an ideal resistive DC circuit.
Enter the values above and select Calculate result.
Formula
V = I × R; P = V × I
Worked example
For 12 V across 600 Ω, I = 12 / 600 = 0.02 A (20 mA). Power in the resistor is 0.24 W.
Engineering notes
Use consistent units. Enter amps rather than milliamps, and remember that Ohm’s law alone does not model a nonlinear diode or switching regulator.
Always compare calculated values with the actual component datasheet, tolerance stack-up, operating temperature and circuit conditions before applying them to hardware.