Ohm's Law Calculator

Instantly calculate voltage, current, resistance, and power with our real-time bidirectional calculator. Perfect for engineers, students, and electronics enthusiasts.

Electrical Parameters

Enter any two values to calculate the others

Volts
Amps
Ohms
Watts

Calculation Results

Real-time computed values

Voltage
0.00 V
Current
0.00 A
Resistance
0.00 Ω
Power
0.00 W

Ohm's Law Formulas

Voltage (V)
V = I × R
Current (I)
I = V ÷ R
Resistance (R)
R = V ÷ I
Power (P)
P = V × I

Master Electrical Calculations with Ohm's Law

Ohm's Law is the fundamental principle governing electrical circuits, discovered by German physicist Georg Ohm. It defines the relationship between voltage (V), current (I), and resistance (R) in an electrical circuit. This relationship is expressed by the simple equation: V = I × R.

Our Ohm's Law Calculator provides instant, bidirectional calculations for all four electrical parameters:

  • Voltage (V) - Electrical potential difference measured in volts
  • Current (I) - Flow of electric charge measured in amperes
  • Resistance (R) - Opposition to current flow measured in ohms
  • Power (P) - Rate of energy transfer measured in watts

Why Use Our Ohm's Law Calculator?

Real-Time Calculations

Get instant results as you type with our bidirectional calculation engine.

Fully Responsive

Works perfectly on any device - desktop, tablet, or smartphone.

High Performance

Optimized for speed with no external dependencies.

Completely Free

No signup required, no hidden fees, no limitations.

Practical Applications

Understanding and applying Ohm's Law is essential for:

  • Designing and analyzing electrical circuits
  • Troubleshooting electronic devices
  • Selecting appropriate resistors and components
  • Calculating power consumption and efficiency
  • Electrical engineering projects and education
  • DIY electronics and hobbyist projects

Frequently Asked Questions

Ohm's Law states that the current through a conductor between two points is directly proportional to the voltage across the two points and inversely proportional to the resistance between them. The formula is expressed as V = I × R, where V is voltage, I is current, and R is resistance.

Our calculator uses precise mathematical formulas to ensure accuracy. However, the results are as accurate as the values you input. The tool performs calculations with up to 10 decimal places but displays results rounded to two decimal places for readability.

Yes! Power (P) is calculated using the formula P = V × I. Our calculator automatically computes power when you provide any two of the following: voltage, current, or resistance. You can also enter power and another value to calculate the remaining parameters.

Absolutely! Our Ohm's Law Calculator is 100% free to use. There are no hidden fees, no registration requirements, and no usage limits. We believe in providing valuable tools to the engineering and educational community without barriers.

Yes, our calculator is fully responsive and works perfectly on all devices including smartphones and tablets. The interface automatically adjusts to provide the best user experience regardless of screen size.