Electrical Power Calculator
Calculate electrical power, current, voltage, and resistance. Analyze power consumption and energy costs for AC and DC systems.
Power Calculator
How to Use This Calculator
Select Calculation Type
Choose which electrical parameters you have: voltage & current, voltage & resistance, or current & resistance. The calculator will compute the missing values using Ohm's law.
Choose Electrical System
Select DC for direct current systems, or AC single/three-phase for alternating current systems. AC systems will include power factor calculations.
Enter Known Values
Input the electrical parameters you know. For voltage, enter in volts (V). For current, enter in amperes (A). For resistance, enter in ohms (Ω).
Set Power Factor (AC only)
For AC systems, enter the power factor (0-1). A power factor of 1.0 represents purely resistive load, while lower values indicate reactive components.
Review Results
The calculator shows power consumption, all electrical parameters, energy usage, and estimated electricity costs. View the breakdown of real, apparent, and reactive power for AC systems.
Analyze Energy Costs
Review daily, monthly, and yearly energy consumption estimates along with cost calculations to understand the financial impact of your electrical usage.
Electrical Power Tips
Use Ohm's law (P = V × I, V = I × R, P = V²/R) to understand the relationship between power, voltage, current, and resistance.
Power factor is crucial for AC systems - a low power factor means inefficient power usage and higher electricity costs.
Three-phase systems are more efficient for high-power applications and industrial use.
Always consider safety when working with electrical systems - high voltage and current can be dangerous.
Energy-efficient devices have higher power factors and consume less reactive power.
Monitor your power consumption to identify energy-saving opportunities and reduce electricity bills.
Resistive loads (heaters, incandescent bulbs) have power factor = 1, while inductive loads (motors) have lower power factors.
Use proper wire sizing based on current calculations to prevent overheating and voltage drops.
Power quality issues can be identified by analyzing the relationship between real, apparent, and reactive power.
Regular electrical system maintenance ensures optimal efficiency and safety.