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Engineering

Capacitor charge and energy

Calculate the charge and electrical energy stored in an ideal capacitor.

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01

Your inputs

The starting values are an example.

Decimals: 12.5 · Thousands: 1,234.56. Follow the field instructions for lists.

02

Your result

Enter your values and select Calculate.

Your calculation will appear here.

Your result will include the relevant values and units.

Understand the calculation

Formula and example

How it is calculated

Q = C × U; E = ½ × C × U²

Worked example

100 µF at 12 V stores 1,200 µC of charge and 7.2 mJ of energy.

Things to check

  • Capacitance is converted from microfarads to farads before calculation.
  • Doubling the voltage quadruples the energy if the capacitance remains unchanged.