What is the formula to calculate the compression ratio?

The compression ratio is calculated using the formula:

[ \text{Compression Ratio} = \frac{\text{Volume of Cylinder at Bottom Dead Center (BDC)}}{\text{Volume of Cylinder at Top Dead Center (TDC)}} ]

This ratio indicates how much the air-fuel mixture is compressed in the cylinder of an internal combustion engine, with a higher ratio generally leading to improved efficiency and power output.