⚡ Ohm's Law Calculator
Calculate V, I, R using Ohm's Law
Enter any two values to calculate the third.
How Ohm's Law Calculation Works
Formula
V = I × R; P = V × I
- 1Enter any two of the three values: voltage (V), current (I), or resistance (R).
- 2The calculator determines which value is missing.
- 3Using Ohm's Law (V = I × R), the missing value is calculated.
- 4Power (P) is also calculated using P = V × I.
- 5Results are displayed with the complete relationship between all values.
About Ohm's Law Calculator
Calculate voltage, current, or resistance using Ohm's Law (V=IR). Enter any two values to find the third, plus power calculation (P=VI).
Frequently Asked Questions
What is Ohm's Law?
Ohm's Law states that voltage equals current times resistance (V = IR). It's the fundamental relationship in electrical circuits, discovered by Georg Ohm in 1827.
What are the units?
Voltage is measured in volts (V), current in amperes (A), and resistance in ohms (Ω). Power is in watts (W). 1 watt = 1 volt × 1 ampere.
When does Ohm's Law not apply?
Ohm's Law applies to 'ohmic' materials where resistance is constant. It doesn't apply to diodes, transistors, or other non-linear components where resistance changes with voltage or current.