Calculate the reactance XC. Choosing a capacitor C and frequency f is best.
Capacitive reactance (symbol XC) is a measure of a capacitor's opposition to
AC (alternating current). Like resistance it is measured in ohms, but
reactance is more complex than resistance because its value depends on the
frequency (f) of the electrical signal passing through the capacitor as well
as on the capacitance, C.
Capacitive reactance, XC = 1 / (2 × π × f × C)
where: XC = reactance in ohms (ohm), f = frequency in hertz (Hz), C = capacitance in farads (F)
The reactance XC is large at low frequencies and small at high frequencies.
For steady DC which is zero frequency, XC is infinite (total opposition),
hence the rule that capacitors pass AC but block DC.
For example a 1 µF capacitor has a reactance of 3.2 kΩ for a 50 Hz signal, but
when the frequency is higher at 10 kHz its reactance is only 16 Ω.
Capacitance C, frequency f, and capacitive reactance XC
Enter the values for capacitance and frequency, then press "calculate".