Calculate DC power, current, or voltage by entering any two values to find the missing variable using A/mA/kA, V/kV/MV, or W/kW/MW units.
Customize This Calculator
Build your own version. Describe what you want changed, added, or compared.
- All Physics Calculators
- All Electrical Calculators
- AC to DC Voltage Calculator
- BLDC Motor Power Calculator
- DC Motor Torque Calculator
DC Power Formula
The DC power calculator uses the basic direct-current power relationship between current, voltage, and power.
- P = power, measured in watts (W), kilowatts (kW), or megawatts (MW)
- I = current, measured in amperes (A), milliamperes (mA), or kiloamperes (kA)
- V = voltage, measured in volts (V), kilovolts (kV), or megavolts (MV)
To calculate power, enter current and voltage. The calculator multiplies amps by volts and returns the result in your selected power unit.
To calculate current, enter power and voltage. The calculator divides power by voltage and returns the result in your selected current unit.
To calculate voltage, enter power and current. The calculator divides power by current and returns the result in your selected voltage unit.
All calculations are converted through base units first: amps, volts, and watts.
DC Power Unit Conversions
| Quantity | Unit | Base-unit equivalent |
|---|---|---|
| Current | 1 mA | 0.001 A |
| Current | 1 kA | 1,000 A |
| Voltage | 1 kV | 1,000 V |
| Voltage | 1 MV | 1,000,000 V |
| Power | 1 kW | 1,000 W |
| Power | 1 MW | 1,000,000 W |
Common DC Power Values
| Current | Voltage | Power |
|---|---|---|
| 1 A | 5 V | 5 W |
| 2 A | 12 V | 24 W |
| 10 A | 24 V | 240 W |
| 50 A | 48 V | 2,400 W or 2.4 kW |
DC Power Examples
Example 1: Calculate power
You have a DC circuit with 12 V and 3 A.
The power is 36 W.
Example 2: Calculate current
You have a 240 W DC load connected to a 24 V supply.
The current is 10 A.
DC Power Calculator FAQ
What is DC power?
DC power is electrical power in a direct-current circuit. In a DC circuit, current flows in one direction. Power is found by multiplying voltage by current, so a 12 V circuit carrying 5 A uses 60 W.
Is DC power the same as AC power?
Not always. For simple DC calculations, power is voltage times current. AC power can require extra values such as power factor, RMS voltage, RMS current, and phase angle. This calculator is for DC power calculations, not AC apparent or real power calculations.
Why do I need to enter exactly two values?
The formula has three variables: power, current, and voltage. If you know any two, the third can be calculated. If fewer than two values are entered, there is not enough information. If all three are entered, there is no missing value to solve for.
