Calculate inductive reactance and the current an inductor passes at a given frequency.
Inductive reactance is proportional to frequency, so an inductor passes DC freely and blocks high frequencies. That behaviour is what makes inductors useful as chokes and in low-pass filtering. A mains-frequency choke becomes almost an open circuit at switching frequencies, which is why the same component behaves so differently in a power supply.
Inductive Reactance
X_L = 2πfL; I = V ÷ X_L
X_L = 2πfL; I = V ÷ X_L Inductive reactance is proportional to frequency, so an inductor passes DC freely and blocks high frequencies. That behaviour is what makes inductors useful as chokes and in low-pass filtering.
A mains-frequency choke becomes almost an open circuit at switching frequencies, which is why the same component behaves so differently in a power supply.
This calculator takes 3 inputs: Inductance, Frequency, Applied voltage. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.