Ohm's Law Calculator

Calculate voltage, current, resistance, and power using Ohm's Law equations

Ohm's Law Calculator

Calculate voltage, current, resistance, and power using Ohm's Law equations. Provide any 2 values to get the other values in the equations V = I × R and P = V × I.

Electrical Values

📊 Calculation Results

📚 Understanding Ohm's Law

Basic Formula

Ohm's Law states that V = I × R, where V is voltage in volts, I is current in amperes, and R is resistance in ohms.

Power Calculation

Electrical power can be calculated using P = V × I, P = V²/R, or P = I² × R, depending on which values you know.

Practical Applications

Use Ohm's Law for circuit design, troubleshooting electrical problems, and calculating safe operating parameters for electrical devices.

What is Ohm's Law?

Ohm's Law states that the current through a conductor between two points is directly proportional to the voltage across the two points. This fundamental principle is true for many materials over a wide range of voltages and currents, and the resistance and conductance of electronic components made from these materials remain constant.

Ohm's Law is valid for circuits that contain only resistive elements (no capacitors or inductors), regardless of whether the driving voltage or current is constant (DC) or time-varying (AC).

The Three Forms of Ohm's Law

V = I × R

Voltage equals current times resistance

I = V / R

Current equals voltage divided by resistance

R = V / I

Resistance equals voltage divided by current

Power Formulas

P = V × I

Power equals voltage times current

P = V² / R

Power equals voltage squared divided by resistance

P = I² × R

Power equals current squared times resistance