Ohm’s Law Calculator
Fill in any two of voltage, current, resistance and power and get the other two.
V = I × R and P = V × I. Any two known values determine the rest: for example R = V ÷ I, P = V² ÷ R and I = √(P ÷ R).
Results are estimates for planning and learning. Check important numbers against your own data and a qualified professional. Everything is calculated in your browser; nothing you enter is sent anywhere.