Ohm's law calculator
Enter any two of voltage, current and resistance: the third value and the power are computed instantly.
Leave the value to compute empty.
V
mA
Ω
- Voltage
- 5 V
- Current
- 22.73 mA
- Resistance
- 220 Ω
- Power
- 113.6 mW
Formula
V = I × R · P = V × I
Ohm's law links the voltage across a resistor to the current flowing through it. The dissipated power tells you which resistor rating to buy: 1/4 W is fine below 0.25 W.
Check your result in a real circuit
Wire the circuit in the Circuitly simulator and measure voltage and current with the multimeter — free, no account.
Open the simulator