Toroid Inductance Per Turn Calculator

Toroid Inductance

The quantity of inductance produced by each winding or turn of wire surrounding a toroidal (doughnut-shaped) core is known as toroid inductance per turn.
The physical properties of the toroid, including its size, composition, and number of turns around it, dictate this parameter.

Calculating and optimizing the inductance value in electronic circuits is the main goal of knowing toroid inductance per turn.
It assists designers and engineers in figuring out how many turns are needed to reach a certain inductance value for uses including energy storage, impedance matching, and filtering.

Understanding Toroid Inductance per turn:

Toroidal inductors represent a category of electrical elements employed for the storage of energy within a magnetic field. Widely utilized within electronic circuits, they serve to guarantee both low frequencies and significant inductance values.


  • Transformer Design
  • Inductive Components
  • Power Supply Filtering
  • RF Circuits
  • Filter out high-frequency noise and interference.
  • Regulate voltage and current.
  • Store energy for later use.
  • Provide a high degree of isolation between circuits.

The Advantages of Toroid Inductors:

High inductance per unit of turns.

High current-carrying capacity.

Low noise and interference.

High degree of isolation between circuits.

The Disadvantages of Toroid Inductors:

High cost.

Limited availability of suitable core materials.

Limited frequency range.

May require additional components for proper operation.

Use this handy online electrical calculator to determine the inductance per turn of a toroidal inductor. When large inductance is required at low frequencies, ring-shaped coil inductors, also known as toroidal inductors, are frequently used. Toroid inductors can efficiently manage bigger currents since they have more turns.

Note : Don’t end with comma ( , )

Core width (h)
Outer diameter (d1)
Inner diameter (d2)
Relative permeability (μr)
Number of turns (N)


\[L = 2⋅N^2⋅μ_r ⋅h⋅ln\frac{d_1}{d_2}\]
\[A_e = \frac{h}{2}⋅(d_1-d_2)\]
\[L_e = \frac{π⋅(d1−d2 )​}{ln(\frac{d_1}{d_2})}\]
\[V_e = A_e⋅L_e\]
\[\frac{B}{I} = \frac{0.4π⋅μr⋅N}{L_e}\]


  • L = Inductance
  • N = number of turns
  • μr = Relative permeability
  • h = Core width
  • d1 = Outer diameter
  • d2 = Inner diameter
  • Ae = Effective core area
  • Le = Effective core length
  • Ve = Effective core volume
  • B/I = Flux Density per Amp

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