Inductance Calculator

Select the box with the geometry that you would like to calculate. The round-wire geometries are loops of wire with various shapes. The transmission line geometries are cross sections and the values calculated are the inductance per unit length.

In all cases, the current is assumed to flow in the outer surface of the conductors. The approximate formulas used to calculate the inductance are provided along with restrictions on the relative size of the various parameters. These formulas can be found in various texts and most of them are derived in the book "Inductance Calculations" by F. W. Grover.


Round-Wire Loop Geometries Transmission Line Geometries
Diagram of a square with side length labeled as 'W'.
Square Loop
Diagram of two circles labeled 'a,' with a distance 'd' between them.
Twin Lead
rectangular loop
Rectangular Loop
wire over ground
Round Wire over a Ground Plane
circlular loop
Circular Loop
vertical traces
Two Vertically Spaced Traces
equilateral triangle loop
Equilateral Triangle Loop
trace over ground
Wide Trace over Ground Plane
isosceles triangle loop
Isosceles Triangle Loop
coplanar traces
Coplanar Traces