Physics

Instant, private, and free

Electrical Power Calculator.

Calculate DC electrical power from voltage and current.

On-device calculationNo signup

Set your values

Results update as you type.

02 / ANSWER

Voltage

Current

Power

0.000000

Educational SI model using the assumptions stated above; verify engineering and safety decisions independently.

Use Cases

Determine power consumption of a DC device

Use this calculator to find out how much power a DC-powered device consumes, helping you estimate energy usage or select appropriate power supplies.

Example: A 12V LED strip drawing 2A consumes 24W.

Verify power ratings in electronics projects

When building or troubleshooting circuits, quickly compute the power to ensure components are within safe limits.

Example: Check if a resistor rated for 0.5W can handle 5V and 0.1A (0.5W).

Frequently Asked Questions

How do I calculate DC power using this calculator?: Enter the voltage in volts (V) and the current in amperes (A) into the respective fields. The calculator multiplies them (P = V × I) to give the power in watts (W).
What units does the Electrical Power Calculator use?: The calculator uses volts (V) for voltage and amperes (A) for current. The result is displayed in watts (W), which is the standard unit of power.
Can I use this calculator for AC circuits?: No, this calculator is specifically for DC (direct current) circuits. For AC, power calculation may involve power factor and other factors, so this simple formula is not accurate.

Tips & Common Mistakes

Tips

Ensure voltage and current are in the same unit system (volts and amperes) before calculating.
For DC circuits, power is simply voltage times current; no power factor is needed.
Double-check your measurements: use a multimeter for accurate voltage and current readings.
If you have power and one other quantity, you can rearrange the formula to find voltage or current.

Common Mistakes to Avoid

Using AC values without considering power factor – this calculator is for DC only.
Mixing units, such as millivolts with amperes, without converting to volts first.
Forgetting that the result is in watts; if you need kilowatts, divide by 1000.

Last updated: August 13, 2026

Use Cases

Determine power consumption of a DC device

Use this calculator to find out how much power a DC-powered device consumes, helping you estimate energy usage or select appropriate power supplies.

Example: A 12V LED strip drawing 2A consumes 24W.

Verify power ratings in electronics projects

When building or troubleshooting circuits, quickly compute the power to ensure components are within safe limits.

Example: Check if a resistor rated for 0.5W can handle 5V and 0.1A (0.5W).

Frequently Asked Questions

How do I calculate DC power using this calculator?

Enter the voltage in volts (V) and the current in amperes (A) into the respective fields. The calculator multiplies them (P = V × I) to give the power in watts (W).

What units does the Electrical Power Calculator use?

The calculator uses volts (V) for voltage and amperes (A) for current. The result is displayed in watts (W), which is the standard unit of power.

Can I use this calculator for AC circuits?

No, this calculator is specifically for DC (direct current) circuits. For AC, power calculation may involve power factor and other factors, so this simple formula is not accurate.

Tips & Common Mistakes

Tips

Ensure voltage and current are in the same unit system (volts and amperes) before calculating.
For DC circuits, power is simply voltage times current; no power factor is needed.
Double-check your measurements: use a multimeter for accurate voltage and current readings.
If you have power and one other quantity, you can rearrange the formula to find voltage or current.

Common Mistakes to Avoid

Using AC values without considering power factor – this calculator is for DC only.
Mixing units, such as millivolts with amperes, without converting to volts first.
Forgetting that the result is in watts; if you need kilowatts, divide by 1000.

Use Cases

Determine power consumption of a DC device

Use this calculator to find out how much power a DC-powered device consumes, helping you estimate energy usage or select appropriate power supplies.

Example: A 12V LED strip drawing 2A consumes 24W.

Verify power ratings in electronics projects

When building or troubleshooting circuits, quickly compute the power to ensure components are within safe limits.

Example: Check if a resistor rated for 0.5W can handle 5V and 0.1A (0.5W).

Frequently Asked Questions

How do I calculate DC power using this calculator?

Enter the voltage in volts (V) and the current in amperes (A) into the respective fields. The calculator multiplies them (P = V × I) to give the power in watts (W).

What units does the Electrical Power Calculator use?

The calculator uses volts (V) for voltage and amperes (A) for current. The result is displayed in watts (W), which is the standard unit of power.

Can I use this calculator for AC circuits?

No, this calculator is specifically for DC (direct current) circuits. For AC, power calculation may involve power factor and other factors, so this simple formula is not accurate.

Tips & Common Mistakes

Tips

Ensure voltage and current are in the same unit system (volts and amperes) before calculating.
For DC circuits, power is simply voltage times current; no power factor is needed.
Double-check your measurements: use a multimeter for accurate voltage and current readings.
If you have power and one other quantity, you can rearrange the formula to find voltage or current.

Common Mistakes to Avoid

Using AC values without considering power factor – this calculator is for DC only.
Mixing units, such as millivolts with amperes, without converting to volts first.
Forgetting that the result is in watts; if you need kilowatts, divide by 1000.