Amps to Watts Calculator (and Watts to Amps)
By Santaji GadepatilinUpdated October 27, 2026
Watts measure the real power a load uses, while amps measure the current it draws. The two are linked by voltage — and, for AC loads such as motors, by power factor — so knowing any two lets you find the third when you size fuses, sockets, generators or inverters. This free amps to watts calculator solves for whichever value you leave blank and shows the formula and steps.
How to use the amps to watts calculator
Enter the current and voltage, choose the system and enter the power factor (1 for DC, heaters and kettles). The calculator gives the power in watts. To go from watts to amps, press × on Current and type the watts.
Amps to watts formulas
| System | Power |
|---|---|
| DC | P = V × I |
| Single-phase AC | P = V × I × PF |
| Three-phase AC | P = √3 × VL × I × PF |
Amps to watts chart (PF 1)
| Amps | 12 V | 24 V | 120 V | 230 V |
|---|---|---|---|---|
| 0.5 A | 6 W | 12 W | 60 W | 115.0 W |
| 1 A | 12 W | 24 W | 120 W | 230 W |
| 2 A | 24 W | 48 W | 240 W | 460 W |
| 5 A | 60 W | 120 W | 600 W | 1,150 W |
| 6 A | 72 W | 144 W | 720 W | 1,380 W |
| 10 A | 120 W | 240 W | 1200 W | 2,300 W |
| 13 A | 156 W | 312 W | 1560 W | 2,990 W |
| 15 A | 180 W | 360 W | 1800 W | 3,450 W |
| 16 A | 192 W | 384 W | 1920 W | 3,680 W |
| 20 A | 240 W | 480 W | 2400 W | 4,600 W |
| 25 A | 300 W | 600 W | 3000 W | 5,750 W |
| 32 A | 384 W | 768 W | 3840 W | 7,360 W |
Socket and circuit limits
| Socket / circuit | Max power (approx.) |
|---|---|
| UK 13 A plug (230 V) | 3,000 W |
| India 6 A socket (230 V) | 1,380 W |
| India 16 A socket (230 V) | 3,680 W |
| US 15 A outlet (120 V) | 1,800 W (1,440 W continuous) |
| US 20 A circuit (120 V) | 2,400 W (1,920 W continuous) |
High-power appliances such as kettles, heaters, geysers and air conditioners should use suitably rated sockets.
Battery systems
For 12 V and 24 V systems (cars, solar, boats), current is high for modest power: a 1,200 W inverter at 12 V draws about 100 A from the battery, plus losses. Use thick cables and fuses close to the battery.
Watts, VA and power factor
For AC loads with a power factor below 1 (motors, some electronics), the real power in watts is lower than volts × amps. That product is the apparent power in VA — see the kVA to kW converter.
Frequently asked questions
How many watts is 1 amp?
It depends on voltage. At 230 V it is 230 W; at 120 V it is 120 W; at 12 V it is 12 W (for DC or unity power factor).
How many watts can a 16 A socket supply?
About 3,680 W at 230 V. Many appliances are limited to a little less for continuous use.
How many amps is 2,000 watts?
About 8.7 A at 230 V or 16.7 A at 120 V.