Parallel Plate Capacitance Calculator

Calculate the capacitance between two parallel plates by entering the plate area, separation distance between the plates, and the dielectric constant below.

Capacitance Results:

  μF
  pF


How to Calculate Capacitance

Two plates aligned in parallel with a dielectric between them has capacitance, or the ability to store an electric charge. This capacitance can be found using this formula:

C = 0Ad

The capacitance C in farads is equal to the dielectric constant k times the relative permittivity ε0 times the area A divided by the separation distance d.

ε0 is equal to the relative permittivity of space, or 8.854 × 10-12.

k is the dielectric constant, and is equal to the relative permittivity of of the dielectric. Free space has the value of 1.

A is equal to the area of each plate in square meters.

d is equal to the distance between each plate in meters.

For example, let’s calculate the capacitance of a parallel plate capacitor with a plate area of 0.25 square millimeters and a distance between the plates of 0.005 millimeters. We’ll use a dielectric constant of 1.

Start by converting millimeters to meters.

0.25 mm2 ÷ 1,000,000 = 0.00000025 m2
0.005 mm ÷ 1,000 = 0.000005 m

Next, solve the formula.

C = 1 × 0.000000000008854 × 0.000000250.000005
C = 0.00000000000000000221350.000005
C = 0.0000000000004427 F

Thus, the capacitance is equal to 4.427 × 10-13 F, or 0.4427pF.