 # Designing a single-layer air-cored coil

This calculator will help you to perform the calculation of an air-cored coil. The formula used in the calculator is sufficiently accurate for inductances not exceeding tens of microhenres. If you need greater inductance you should use more adequate methods. You can:
• enter the number of turns n, the coil diameter D and the wire diameter d, and the calculator will compute an estimated value of inductance L
• enter the number of turns n, the wire diameter d and the inductance L, and the calculator will compute an estimated value of coil diameter D
• enter the coil diameter D, the wire diameter d and the inductance L, and the calculator will compute an estimated number of turns n
Additionally the calculator will compute the winding total length, the total wire length and the estimated resistance of the winding. If you enter the value of frequency f, the calculator will estimate the expected Q-factor for the coil. Don't forget to select proper units for all the fields!
There is a good practise to wind 10% more turns than calculated. Any corrections will then be easier.

n =

D =

d =

L =

Enter frequency if you want to estimate Q-factor for the coil:

f =

Winding wire total length:

Winding total length:

Est. Q-factor:

Est. winding resistance (copper) (R[Ω]):

Est. reactance (X[Ω]):

Est. impedance (Z[Ω]):
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[ekalk]© Sławek Wernikowski, 2012-2018. Set of useful interactive calculators for electronics constructors and hams.

All suggestions and comments are always welcome.

[3.40 2020-08-22][]