# Coil Inductance Calculator

## This calculator computes the inductance of a wire coil.

cm
cm2
cm

H/m

### Overview

The coil is the most recognizable form of an inductor. This tool is designed to calculate the inductance of a coil of wire given the length of the coil, the number of turns, the loop radius, and the permeability of the core material.

### Equation

$$L_{coil} = \frac{ \mu_{r} \mu_{0} N^{2} A}{l} = \frac{ \mu_{r} \mu_{0} N^{2} \pi r^2}{l}$$

Where:

$$L_{coil}$$ = inductance of the coil in henries (H)

$$\mu_{r}$$ = relative permeability of the core (dimensionless)

$$\mu_{0}$$ = permeability of free space = $$4 \pi × 10^{−7}$$ (H/m)

$$N$$ = number of turns

$$A$$ = coil area (m2)

$$r$$  = coil radius (m)

$$l$$ = coil length (m)