Coaxial Cable Calculator

Calculate the characteristic impedance $Z_0$ using: $$ Z_0 = \frac{60}{\sqrt{\epsilon_r}} \ln\!\left(\frac{D}{d}\right) $$

* Enter the inner diameter of the outer conductor ($D$) and the outer diameter of the inner conductor ($d$) in the same unit (e.g., mm), and the relative permittivity $\epsilon_r$ of the dielectric.

Step 1: Enter Parameters

Inner Diameter of Outer Conductor, $ D $ (mm):

e.g., 10 mm

Outer Diameter of Inner Conductor, $ d $ (mm):

e.g., 2 mm

Relative Permittivity, $ \epsilon_r $:

e.g., 2.25 (typical for polyethylene)

Step 1: Enter Parameters

Calculated Characteristic Impedance