โกOhm's Law Calculator
Enter any two of voltage, current, resistance, or power โ the rest are solved instantly with a formula triangle and steps shown.
Free Ohm's Law Calculator
Need to solve a circuit problem fast? Our free Ohm's Law Calculator finds voltage, current, resistance, or power the moment you enter any two related values. Type in what you know, and get the answer instantly โ complete with a visual formula triangle so you can see exactly how the values relate.
Unit conversions are built in, so you can mix volts and millivolts, amps and milliamps, or ohms and kilohms without doing the math yourself. Every result comes with the formula used and the substitution shown step by step, making it easy to check your circuit homework or verify a real-world measurement.
Whether you're a student learning basic electronics or an engineer double-checking a quick calculation, this tool gives you accurate answers with the working shown. No sign-up, no downloads, no limits. See the About page or the FAQ for more.