There are a few factors that affect the performance of an inductor. The major ones are discussed below.
The length of the inductor coil is inversely proportional to the inductance of the coil. If the length of the coil is more, the inductance offered by that inductor gets less and vice versa.
The cross sectional area of the coil is directly proportional to the inductance of the coil. The higher the area of the coil, the higher the inductance will be.
With the number of turns, the coil affects the inductance directly. The value of inductance gets square to the number of turns the coil has. Hence the higher the number of turns, square of it will be the value of inductance of the coil.
The permeability (μ) of the core material of inductor indicates the support the core provides for the formation of a magnetic field within itself. The higher the permeability of the core material, the higher will be the inductance.