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Compressors are used to compress air to create more efficient combustion in the combustion chamber. They come in two forms: Axial compressor and Centrifugal compressor.

The axial compressor increases the air's kinetic energy and then converts it into pressure energy. It consists of a series of aerofoil section blades, called rotors, mounted on a rotating rotor disc, which accelerate the air towards stationary stator blades. Each set of rotors and stators is known as a stage. An axial flow compressor comprises many stages, with each stage typically providing a pressure rise of about 10% to 20% (1.1 to 1.2:1). The pressure rise per stage is kept small to prevent blade stalling and excessive drag. Consequently, an axial flow compressor requires multiple stages to achieve a usable compression level. Axial flow compressors generally achieve pressure ratios of 35:1 to as high as 50:1.

A centrifugal compressor consists of two main components: the impeller, which rotates to accelerate the air, and the diffuser, which collects and directs the airflow into the manifold. The pressure ratio of a single-stage centrifugal compressor is typically around 4:1, meaning the outlet pressure is approximately four times higher than the inlet pressure.