LC Resonance Calculator

Calculate the resonant frequency of an LC tank circuit, or find the required inductance or capacitance for a target frequency.

Schematic

Reactance at Resonance

Resonant Frequency (fr):
Reactance (XL = XC):
Char. Impedance (Z0):

Reactance vs. Frequency

Resonance Theory

Resonance occurs when the inductive reactance ($X_L = 2\pi f L$) and capacitive reactance ($X_C = \frac{1}{2\pi f C}$) are equal in magnitude but opposite in phase, effectively canceling each other out.

Parallel Tank: Impedance is theoretically infinite at resonance. Used as a band-stop or frequency selector.
Series Tank: Impedance is theoretically zero (only limited by ESR) at resonance. Used as a band-pass filter.
Impedance: The characteristic impedance is $Z_0 = \sqrt{L/C}$.

Configuration:
Resonant Frequency (fr):
Inductance (L):
Capacitance (C):
Calculate:

LC Resonance Calculator

Circuit Parameters

Schematic

Reactance at Resonance

Reactance vs. Frequency

Resonance Theory