Use this electronics calculation for a first-pass component, converter, signal, motor, or sensor estimate when the stated operating conditions and units match the device data.

L1 (H)

Required number input.

L2 (H)

Required number input.

Mutual inductance (H)

Optional number input.

Capacitance (F)

Required number input.

Compute the Hartley tank frequency f = 1 / (2 * pi * sqrt((L1 + L2 + 2M) * C)). The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Oscillation frequency (Hz)

The resulting oscillation frequency returned as a number.

• Oscillator estimates use nominal component values and simplified resonator models. Load capacitance, parasitics, drive level, startup margin, phase noise, temperature, aging, pulling, and amplifier nonlinearities determine the realized frequency and stability.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Check the result against the current datasheet and worst-case operating corners, then verify the circuit or measurement with simulation and bench testing where failure matters.

• Colpitts Frequency

  Compute the Colpitts tank frequency f = 1 / (2 * pi * sqrt(L * C1 * C2 / (C1 + C2))).

• Phase Shift Oscillator

  Compute the oscillation frequency of an RC phase-shift oscillator f = 1 / (2 * pi * sqrt(6) * R * C).

• Resonant Frequency Calculator

  Compute the LC tank resonant frequency f0 = 1 / (2 * pi * sqrt(L * C)), where inductive and capacitive reactances cancel.