Amps to Watts Calculator

Amps to Watts Calculator

Electric current in amps (A) to electric power in watts (W) calculator.

A
V
W
kW
mW

Example Calculation

Problem: Calculate the power consumption of a device that draws 2.5 amps at 120 volts DC.

Solution:
Given: Current (I) = 2.5 A, Voltage (V) = 120 V
Formula: P = I × V
Calculation: P = 2.5 A × 120 V = 300 W

Answer: The device consumes 300 watts of power.

Ampere

Ampere (A) is a unit of electric current. Electric current is the rate of electric charge flow per time unit. One ampere (A) is equal to one coulomb (Q) per second (s).

Watt

Watt (W) is a unit of power. Power is the rate of energy usage per time unit. One watt (W) is equal to one joule (J) per second (S).

DC amps to watts calculation

The power P in watts (W) is equal to the current I in amps (A), times the voltage V in volts (V):

P(W) = I(A) × V(V)
Or
Watts = Amps × Volts

AC single phase amps to watts calculation

The power P in watts (W) is equal to the power factor PF times the phase current I in amps (A), times the RMS voltage V in volts (V):

P(W) = PF × I(A) × V(V)
Or
Watts = PF × Amps × Volts

AC three phase amps to watts calculation

Calculation with line to line voltage

The power P in watts (W) is equal to square root of 3 times the power factor PF times the phase current I in amps (A), times the line to line RMS voltage VL-L in volts (V):

P(W) = √3 × PF × I(A) × VL-L(V)

Calculation with line to neutral voltage

The power P in watts (W) is equal to 3 times the power factor PF times the phase current I in amps (A), times the line to neutral RMS voltage VL-N in volts (V):

P(W) = 3 × PF × I(A) × VL-N(V)

Typical power factor values

Do not use typical power factor values for accurate calculations.

Device Typical power factor
Resistive load1
Fluorescent lamp0.95
Incandescent lamp1
Induction motor full load0.85
Induction motor no load0.35
Resistive oven1
Synchronous motor0.8

Amps to watts table (120V)

Current (A) Voltage (V) Power (W)
0.1 amps120 volts12 watts
0.2 amps120 volts24 watts
0.3 amps120 volts36 watts
0.4 amps120 volts48 watts
0.5 amps120 volts60 watts
0.6 amps120 volts72 watts
0.7 amps120 volts84 watts
0.8 amps120 volts96 watts
0.9 amps120 volts108 watts
1 amps120 volts120 watts
2 amps120 volts240 watts
3 amps120 volts360 watts
4 amps120 volts480 watts
5 amps120 volts600 watts
6 amps120 volts720 watts
7 amps120 volts840 watts
8 amps120 volts960 watts
9 amps120 volts1080 watts
10 amps120 volts1200 watts

FAQS

1 amp = watts 240v?

At 240V, 1 amp equals 240 watts using the formula P = V × I (Power = Voltage × Current). This calculation applies to resistive loads like heaters, incandescent bulbs, and electric kettles where power factor equals 1.

Answer: To calculate watts from amps, multiply current (amps) by voltage using P = V × I formula. For example: 1 amp × 120V = 120 watts, or 1 amp × 240V = 240 watts depending on your electrical system voltage.

Answer: At 220V, 1 amp equals 220 watts for resistive electrical loads. This voltage is common in many countries and the calculation follows Ohm’s Law: Power (watts) = Voltage (220V) × Current (1 amp).

Answer: 10 amps at 220V equals 2,200 watts (2.2 kW) for resistive loads. This power level is typical for high-demand appliances like electric water heaters, air conditioners, or multiple household devices running simultaneously.

Answer: Use the electrical power triangle: Watts = Volts × Amps, Volts = Watts ÷ Amps, Amps = Watts ÷ Volts. These formulas help calculate any unknown value when you have two known electrical parameters for safe circuit design.

Answer: At 12V DC, 1 amp equals 12 watts, commonly used in automotive, RV, and solar applications. This low-voltage calculation is essential for battery systems, LED lighting, and 12V appliances in mobile or off-grid setups.

16 amp to watts 220V?

Answer: 16 amps at 220V equals 3,520 watts (3.52 kW) for resistive loads. This amperage is typical for dedicated circuits serving electric ovens, large air conditioning units, or electric vehicle charging stations.

Answer: At 440V (industrial voltage), 1 amp equals 440 watts for single-phase resistive loads. This voltage is common in industrial three-phase systems where line-to-line voltage reaches 440V for heavy machinery and large motors.

Answer: You cannot convert amps to watts without knowing the voltage, as watts = volts × amps according to electrical power law. Voltage is essential because the same current at different voltages produces vastly different power outputs.

Answer: DC power calculations use P = V × I directly, while AC power calculations may require power factor consideration: P = V × I × PF. For resistive AC loads, power factor equals 1, making calculations identical to DC.

Answer: A 15 amp circuit at 120V can safely handle 1,440 watts (80% of 1,800W maximum capacity). The National Electrical Code requires continuous loads stay below 80% capacity for safety and code compliance.

Answer: At 120V, 1 amp powers 120-watt devices like LED light strips, small fans, phone chargers, or laptop computers. At 240V, 1 amp can power 240-watt appliances like small space heaters or power tools.