Physics Formulas

Capacitor Charge Formula

Below is the capacitor charge formula for a capacitor in a DC circuit. Before we discuss the capacitor charge formula, let's define what a capacitance (C) is.

Definition of capacitance (C)

Capacitance (C) is defined as the charge stored per unit potential difference.

The formula for the capacitor charge is as follows.

Capacitor Charge Formula


  • Q = charge stored (C)
  • V = applied potential difference (V)
  • C = capacitance (F or Farads)
The combination rules for capacitors in DC circuits

In series, another useful formula for capacitors in DC circuits is:

Capacitor combination rules

The combination rule for capacitors is that in series the combined capacitance (C) of two capacitors in series is given by the above formula for capacitors.

In parallel, the combined capacitance (C) formula is:

Capacitor formula in parallel combination