Inductance of a Straight, Non-magnetic Wire, In Free Space

Wire Size (a)
(AWG, in, or mm)

Length of Wire (b)
(in, or mm)


Any length of wire has some inductance, however, at low frequencies, 1-30 MHz, the added effect of this inductance is usually minimum. At VHF and UHF frequencies the inductance of a wire may have a great effect on a circuit. Now, there is no diagram for this because it is simply a straight round wire in free space. By free space I mean, it is far enough from grounds or other wires so that they have minimum effect.

At VHF frequencies, and above, skin effect will reduce the inductance. The constant, 0.75 will approach infinity, however, skin effect will not reduce the inductance by more than a few percent.

Enter your data below. Internally, all input data is converted to inches for calculation purposes, however, for entry purposes, the dimensions can be mixed or matched.