⚡ Capacitive Reactance Calculator
Calculate the capacitive reactance of a capacitor at a given AC frequency, showing how much it opposes alternating current.
Hz
µF
What capacitive reactance is
Capacitive reactance is the opposition a capacitor presents to alternating current, which decreases as frequency or capacitance increases (unlike a resistor, which opposes current the same at any frequency).
The formula
Capacitive reactance is Xc = 1 / (2πfC), where f is the AC frequency in hertz and C is the capacitance in farads. Higher frequencies or larger capacitors let more current through, resulting in lower reactance.
This calculator is for general electronics and physics education.
Last reviewed August 2026