Coil Inductance Calculator

Coil Inductance Calculator

Calculate the inductance using Wheeler’s formula for a single‐layer air‐core coil: $$ L (\mu H) = \frac{d^2 \, N^2}{18\,d + 40\,l} $$

* Enter the coil diameter and coil length in millimeters (mm) and the number of turns (N). The diameters and lengths are converted to centimeters (cm).

Step 1: Enter Parameters

e.g., 20 turns

e.g., 30 mm

e.g., 10 mm

Formula: $$ L (\mu H) = \frac{d^2 \, N^2}{18\,d + 40\,l} $$
where \( d \) and \( l \) are in centimeters.