We rely on demand and supply-side information to measure the extent of financial inclusion at country level for eighty-two developed and less-developed countries. We postulate that the degree of financial inclusion is determined by three dimensions: usage, barriers and access to financial inclusion. Weights assigned to the dimensions are determined endogenously by employing a two-stage Principal Component Analysis. Our composite index offers a comprehensive measure of the degree of financial inclusion, easy to understand and compute. Issues relating to financial inclusion are a subject of growing interest and one of the major socioeconomic challenges on the agendas of international institutions, policymakers, central banks, financial institutions and governments. The World Bank’s declared objective of achieving universal financial access by 2020 is another example of financial inclusion being recognized as fundamental for economic growth and poverty alleviation. The World Bank’s latest estimates state that half the adult population in the world does not have a bank account in a formal financial institution. However, the concept of financial inclusion goes beyond single indicators, such as percentage of bank accounts and loans and number of automated teller machines (ATMs) and branches. The attempts to measure financial inclusion through multidimensional indices are scarce and incomplete. To the best of our knowledge, literature lacks a comprehensive indicator that can bring together information on financial inclusion by using a statistically sound weighting methodology and takes into account both demand- and supply-side information. Our study aims to fill this gap.