MyWebUtils: Free Online Dev Tools
Ohm's Law Calculator
Enter any two values to calculate the third, plus Power.
V
A
Ω
W
A Guide to Ohm's Law
What is Ohm's Law?
Ohm's Law is one of the most fundamental principles in electronics and electrical engineering. It describes the relationship between three key quantities in a circuit: Voltage (V), Current (I), and Resistance (R).
The law is famously expressed by the formula: `V = I × R`
The Components Explained
- Voltage (V): Measured in Volts (V), it's the electrical potential difference between two points—think of it as the "pressure" that pushes electric charge.
- Current (I): Measured in Amperes (A), it's the rate at which charge flows through a conductor.
- Resistance (R): Measured in Ohms (Ω), it's the measure of opposition to the flow of current.
- Power (P): Our calculator also computes Power, measured in Watts (W), which is the rate at which electrical energy is transferred. It is calculated as `P = V × I`.
How This Calculator Helps
This tool makes it incredibly easy to solve for any unknown variable in Ohm's Law. Simply select which value you want to calculate (Voltage, Current, or Resistance), enter the two known values, and the calculator will instantly find the missing piece, along with the resulting power.
It's an indispensable utility for electronics hobbyists, engineering students, and professional electricians for designing circuits, troubleshooting problems, and verifying calculations.