LC Resonant Frequency Calculator
Solve f₀ = 1/2π√LC any direction, plus characteristic impedance, Q from loss resistance and bandwidth.
Real parts detune the math: every inductor has 1–10 pF of self-capacitance and every layout adds strays, so trimmers exist. High Z₀ (big L, small C) gives high Q but more sensitivity to strays; low Z₀ tanks are stabler but need more drive. Above self-resonance an “inductor” is actually a capacitor — check the SRF on the datasheet.
LC Resonant Frequency Calculator computes resonant frequency, characteristic impedance and Q of an LC pair — solving any direction — free, instant and private in your browser. Radio builders, wireless-power tinkerers and EMC filter designers use it to skip the datasheet algebra: type your numbers, read the answer with the substituted formula shown step by step, and share an exact permalink of the calculation.
About LC Resonant Frequency Calculator
LC Resonant Frequency Calculator computes resonant frequency, characteristic impedance and Q of an LC pair — solving any direction using the standard engineering relation: f₀ = 1/(2π√LC); Z₀ = √(L/C); Q = Z₀/R; BW = f₀/Q. Worked live: 100 µH with 100 pF resonates at 1.59 MHz with Z₀ = 1 kΩ. The result recalculates on every keystroke, the worked-example panel shows your numbers substituted into the formula, and the Copy permalink button encodes the inputs in the URL so a colleague opens exactly your calculation. Everything runs client-side — nothing you type leaves your device.
How to use LC Resonant Frequency Calculator
- 1Enter your values — the tool starts with realistic defaults for this exact use case, so the worked example is meaningful immediately.
- 2Read the live result and the worked-example panel, which substitutes your numbers into the formula step by step.
- 3Adjust any input to compare scenarios, then use Copy result or Copy permalink to share the calculation.
Why use LC Resonant Frequency Calculator?
- ✓Implements the real formula — f₀ = 1/(2π√LC) — with the substitution shown, not a black box
- ✓Built for radio builders, wireless-power tinkerers and EMC filter designers
- ✓Copy result and permalink buttons — share the exact calculation in a README, forum answer or design review
- ✓100% free, no sign-up, runs entirely in your browser (works offline once loaded)
Frequently asked questions
How do you calculate lc resonant frequency?+
Resonant frequency, characteristic impedance and Q of an LC pair — solving any direction follows f₀ = 1/(2π√LC); Z₀ = √(L/C); Q = Z₀/R; BW = f₀/Q. For example, 100 µH with 100 pF resonates at 1.59 MHz with Z₀ = 1 kΩ. The calculator applies the same relation and shows the substituted arithmetic so you can verify every step.
Why doesn't my tank circuit resonate where calculated?+
Strays: every inductor carries 1–10 pF of self-capacitance, layout adds more, and probes add 10–15 pF the moment you measure. High-Z₀ tanks (big L, small C) feel this worst. Design with a trimmer in range, or measure L and C at the working frequency first.
What limits Q in a real LC circuit?+
Almost always the inductor's effective series resistance at frequency (skin effect makes it far higher than the DC reading). Air cores and litz wire push Q to 100–400; small SMD inductors manage 10–50. The capacitor's contribution is usually negligible below VHF if it's NP0/C0G.
Is the LC Resonant Frequency Calculator free and private?+
Yes — completely free with no sign-up or usage limits, and it runs entirely in your browser: the values you enter are never uploaded or stored on a server.
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