Watt Calculator
Enter any two of power, voltage, and current to solve for the third.
Calculate
Enter your values below.
Result
Power (W)
0
Voltage (V)
0
Current (A)
0
Formula used
P = V × I
Example: 120 V at 5 A → power = 600 W.
How to use this calculator
- Enter Power (W), Voltage (V), Current (A).
- Press Calculate to see your result instantly.
FAQ
Frequently asked questions
How many values do I need to enter?
Exactly two — leave the third field blank and it will be calculated.
What is a watt?
The SI unit of power, equal to one joule per second, or one volt times one amp.
How is this related to Ohm's Law?
Power, voltage, current, and resistance are all interconnected — this tool covers the power side of that relationship.
What if I need to convert watts to kilowatts?
Divide by 1,000, or use the Unit Converter's Energy category for related conversions.