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RLC Resonant Frequency, Bandwidth & Q-Factor Calculator

An RLC resonant circuit oscillates at a natural frequency where energy trades back and forth between inductor and capacitor.

Coil inductance in millihenries (mH).

Capacitance in microfarads (µF).

Total series internal resistance in Ohms.

Calculated Result
5032.92 Hz

Resonant Frequency (f₀)

Resonant Frequency (f₀)

5032.92 Hz (5.0329 kHz)

Quality Factor (Q)

6.325

Half-Power Bandwidth (Δf)

795.77 Hz

Angular Frequency (ω₀)

31622.8 rad/s

Damping State

Underdamped (High Q Ringing)

Calculation Breakdown

  1. Angular Frequencyω₀ = 1 / √(L × C) = 31622.8 rad/s
  2. Resonant Frequencyf₀ = ω₀ / (2π) = 5032.92 Hz (5.0329 kHz)
  3. Quality FactorQ = (1 / R) × √(L / C) = 6.325 (Underdamped (High Q Ringing))
  4. Passband BandwidthΔf = f₀ / Q = 795.77 Hz

Current Response vs Frequency (Peak at 5.03 kHz)

Interactive visualization based on your current inputs

Response (%)
0.02550751003 kHz4.5 kHz5.03 kHz (f0)5.5 kHz7 kHzFrequency (kHz)Relative Response (%)

What Is the RLC Resonant Frequency, Bandwidth & Q-Factor Calculator?

An RLC circuit combines a resistor, an inductor, and a capacitor to create electrical harmonic resonance.

How Does the RLC Resonant Frequency, Bandwidth & Q-Factor Calculator Work?

Energy stored in the inductor magnetic field alternates cyclically with electric field energy in the capacitor.

RLC Resonant Frequency, Bandwidth & Q-Factor Calculator Formula & Variables

The core mathematical equation utilized by this calculator is expressed as:

f_0 = \frac{1}{2\pi \sqrt{L \cdot C}}, \quad Q = \frac{1}{R} \sqrt{\frac{L}{C}}, \quad \Delta f = \frac{f_0}{Q}

Resonant frequency f0 occurs when inductive and capacitive reactances are equal; Q factor dictates damping and bandwidth.

How to Use the RLC Resonant Frequency, Bandwidth & Q-Factor Calculator

  1. Specify inductance in millihenries (mH).
  2. Provide capacitance in microfarads (µF).
  3. Input series resistance in Ohms.

Step-by-Step Example Calculation

10 mH / 0.1 µF Radio Tuning Circuit

Input Values:

inductanceMh:10.0
capacitanceUf:0.1
resistanceOhms:50.0
Worked Steps: With 10 mH and 0.1 µF, the circuit resonates at 5.033 kHz (5033 Hz) with Q = 6.325 and a 3-dB bandwidth of 795.8 Hz.

Understanding Your Result

Resonant Frequency (f₀): Peak oscillation frequency in Hz and kHz.

Quality Factor (Q): Ratio of stored energy to dissipated energy per cycle.

Bandwidth (Δf): Frequency width where power remains within 50% (-3dB) of peak.

Factors That Affect the Result

  • Inductance and capacitance set the frequency; series resistance sets peak sharpness and damping.

When Should You Use This Calculator?

  • AM/FM radio receiver front-ends, induction heating coils, audio cross-over networks, and RFID tags.

Assumptions & Limitations

  • Assumes linear passive components without frequency-dependent core eddy current saturation.

Frequently Asked Questions

Calculation Accuracy & Reference Note

Standard electrical engineering alternating current formulation.

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