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Electrical Power Calculator

Electrical power from any two of voltage, current and resistance, with the energy it uses over time.

Physics & EngineeringTop 100 · #92Runs in your browser

Result…

You know
V
A
h

For the energy used.

 

…

How it's calculated

P = V × I
P = I² × R
P = V² ÷ R
E (kWh) = P (kW) × t (h)

Electrical power is the rate at which a circuit turns electrical energy into heat, light or motion. These formulas are exact for DC and for resistive AC loads (heaters, kettles) using RMS values; motors and electronics on AC also have a power factor, so their real power is lower than V × I.

Your numbers, step by step

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