Energy and charge stored in a capacitor

The energy and charge stored in a capacitor can be calculated if the voltage and capacitance are known.


The following formulas can be used to calculate the energy and charge in a capacitor. You can also calculate the voltage or capacitance if the other values are known.



The following formula is needed if you want to calculate the capacitance when only the stored energy and charge are known:

E is the symbol for energy and is measured in joule (J).
C is the symbol for capacitance and is measured in farad (F).
V is the symbol for voltage and is measured in volt (V).
Q is the symbol for charge and is measured in coulomb (C).