Data envelopment analysis (DEA) is a nonparametric linear programming technique that evaluates the relative efficiency of a set of decision-making units (DMUs) that use multiple inputs to produce multiple outputs. DEA is widely used in various fields, including finance, healthcare, education, and manufacturing. DEA is especially useful for evaluating the performance of DMUs where there are no clear benchmarks or when traditional statistical methods are inappropriate. This abstract provides an overview of DEA analysis for Indian airlines, including its basic principles, mathematical formulations, and applications. DEA can help decision-makers identify inefficiencies in their operations and provide insights into how to improve performance.