Ohm's Law Calculator

Calculate voltage, current, resistance and power with our comprehensive Ohm's Law Calculator. Perfect for electrical engineering students and professionals.

Ohm's Law Calculator

Voltage Unit
Current Unit
Resistance Unit

Calculating...

Ohm's Law Calculation Result

Result will appear here
V = I × R
0 V
Voltage
0 A
Current
0 Ω
Resistance

Interactive Simulation

Voltage 0 V
Resistance 10 Ω

Live Circuit Diagram

R = 10Ω V = 0V

Adjust the sliders to see how voltage and resistance affect the current in the circuit.

Calculating...

Power Calculation Result

Result will appear here
P = V × I = I² × R = V² / R
0 V
Voltage
0 A
Current
0 W
Power

Calculating...

Series Resistance Result

Result will appear here
R_total = R1 + R2 + R3 + R4

Series Circuit Diagram

R1 R2 R3 R4

Calculating...

Parallel Resistance Result

Result will appear here
1/R_total = 1/R1 + 1/R2 + 1/R3 + 1/R4

Parallel Circuit Diagram

R1 R2 R3

About 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. It is usually formulated as:

V = I × R

Where:

  • V = Voltage (volts)
  • I = Current (amps)
  • R = Resistance (ohms)

Power in Electrical Circuits

Power in electrical circuits can be calculated using:

  • P = V × I
  • P = I² × R
  • P = V² / R

Series and Parallel Circuits

Series Circuits: The total resistance is the sum of all individual resistances:

R_total = R1 + R2 + R3 + ...

Parallel Circuits: The reciprocal of the total resistance is the sum of the reciprocals of all individual resistances:

1/R_total = 1/R1 + 1/R2 + 1/R3 + ...

Usage Instructions

  • Select the appropriate tab for your calculation
  • Enter at least two known values
  • Click the calculate button to get results
  • Use the interactive sliders to visualize relationships
  • Hover over info icons for additional guidance