Education
Amps to Watts Calculator
Last updated: May 31, 2026
Written by Blake Boege
An amps to watts calculator is an electrical engineering utility that computes electric power in watts based on the current drawing rate in amperes and the voltage of the circuit. The tool handles DC systems using the direct product of current and voltage, and AC systems by factoring in the electrical power factor and phase configurations (single-phase vs. three-phase). Electricians and homeowners use it to size circuits and avoid overloading breakers.
Convert electric current in amperes to power in watts. Supports DC, AC single-phase, and AC three-phase circuits.
Quick Answer
Convert electrical current in amperes to power in watts. Enter current, voltage, and power factor to calculate watts instantly.
Current Type
Formula Used
Watts = Amps × Volts = 10 × 120
Power (Wattage)
1,200 W
At 120V (DC)
This calculator converts electric current in amperes to electric power in watts. For AC circuits, it adjusts for the power factor representing efficiency and phase displacement.
How it works
Electric Power Formulas
The formulas used to convert amperes (A) to watts (W) depend on the type of electrical system:
Direct Current (DC)
Watts = Amps × Volts
Alternating Current (AC) Single-Phase
Watts = Power Factor × Amps × Volts
Alternating Current (AC) Three-Phase
Watts = 1.732 × Power Factor × Amps × Volts
Related electrical calculators
Related Calculators
More tools from Education
Frequently asked questions
To convert amps to watts, multiply the current in amps by the voltage in volts. For direct current (DC) circuits, the formula is W = A × V. For alternating current (AC) circuits, multiply the current and voltage by the power factor: W = PF × A × V for single-phase systems.
For three-phase AC circuits, the formula is: Watts = 1.732 × Power Factor × Amps × Volts, where 1.732 represents the square root of 3, and Volts is the line-to-line voltage.
If an appliance draws 10 amps on a standard 120V single-phase household outlet (with a typical power factor of 1.0), the calculation is: Watts = 10 A × 120 V × 1.0 = 1,200 W.
Watts represent 'real power' that actually performs work (like heating or mechanical rotation). Volt-amperes represent 'apparent power', which is the simple product of current times voltage. In AC circuits, Real Power (W) = Apparent Power (VA) × Power Factor.
Related calculators
Education
Time to Decimal Calculator
Convert hours and minutes (HH:MM) to decimal hours and back for timesheets, payroll, or math problems.
Education
Deadline Calculator
Calculate a target deadline date by adding calendar days or business days to a starting date.
Education
Audiobook Calculator
Calculate your actual listening time and time saved when playing back audiobooks or podcasts at faster speeds (1x to 3x).