I would like to calculate the impedance of a via. “Calculator Tools” doesn’t seem to have that in the high-speed/transmission-lines section, however there is a “Via Size” that is in the power-current-isolation section and it includes a calculated “Reactance” field. Calculator Tools | 8.0 | English | Documentation | KiCad shows:

If I calculate Sqrt[1.20723nH / 0.599508pF] I get 44.9 ohms. But the calculator shows “Reactance 3.8 ohms”

- is this a bug in the calculator that I should report?
- or do I misunderstand “reactance”, and it is something other than the via’s characteristic impedance?