Southeast Asian countries have a wide range of Human Development Index (HDI) values. HDI is based on a measure of social and economic development. When comparing HDI values, Brunei and Singapore are at the top. There is a tremendous gap when comparing Brunei and Singapore's Gross National Income to the rest of the countries. Singapore also has the highest life expectancy and years of schooling. As of now, it is the most developed country in Southeast Asia.
*The Human Development Index is composed of gross national income (GNI) per capita, life expectancy, and mean years of schooling.