How can I calculate the coil's self-inductance?

To calculate a coil's self-inductance, you can use the formula L ( N A) / l, where L is the self-inductance, is the permeability of free space, is the relative permeability of the core material, N is the number of turns in the coil, A is the cross-sectional area of the coil, and l is the length of the coil.