Ohm's Law Calculator

Ohm's Law Calculator is the essential electrical engineering tool that instantly calculates voltage, current, resistance, and power. Simply enter any two values and get the remaining two results automatically.

Whether you are an electrical engineering student studying circuit theory, a licensed electrician working on-site, or a DIY electronics hobbyist building your next project, this calculator makes Ohm's Law calculations quick and effortless.

▶ How It Works
Enter any two of the four electrical values — Voltage (V), Current (I), Resistance (R), or Power (P) — and the app instantly computes the other two. No need to memorize complex formulas or switch between multiple tools.

▶ Key Features
• Instant Calculation – Input 2 values, get 2 results immediately
• All Formulas Supported – V=IR, P=VI, P=I²R, P=V²/R and more
• Formula Display – See which formula was used for each calculation
• Clear Unit Labels – Volts (V), Amps (A), Ohms (Ω), Watts (W)
• Calculation History – Access your last 5 calculations anytime
• One-Tap Copy – Tap any result to copy it to your clipboard
• Clean Interface – Simple, intuitive design with no clutter

▶ Supported Calculations
This Ohm's Law calculator covers every combination of the four fundamental electrical quantities:
- Voltage and Current → calculates Resistance and Power
- Voltage and Resistance → calculates Current and Power
- Voltage and Power → calculates Current and Resistance
- Current and Resistance → calculates Voltage and Power
- Current and Power → calculates Voltage and Resistance
- Resistance and Power → calculates Voltage and Current

▶ Perfect For
• Electrical engineering students and teachers
• Electricians and electrical technicians
• Electronics hobbyists and makers
• Circuit design and analysis
• Electrical certification exam preparation
• Quick on-site voltage, current, and resistance calculations

▶ Why This Calculator
Most electrical calculators are overcomplicated. This app focuses on doing one thing perfectly — solving Ohm's Law. The clean interface lets you get your answer in seconds, and the formula display helps you understand the math behind each result.

Ohm's Law Calculator supports 37 languages.

Simplify your electrical calculations with a tool built for clarity.