Debt to GDP Ratio by Country 2018

Japan, with its population of 127,185,332, has the highest national debt in the world at 235.96% of its GDP (although, notably, Japan is also one of the world's largest economies). This is followed by Greece, which is still recovering from the effects of its economic crisis and subsequent bailout, at 191.27%. Venezuela, which is currently undergoing serious economic difficulties, is also in the top five countries with the highest national debt, with a debt to GDP ratio of 161.99%. Several African countries also have high national debts, including Sudan (176.49%), Eritrea (129.43%) and Gambia (111.45%).

Of the world's major economic powers, the United States has the highest national debt at 108.02% of its GDP. China, the world's second-largest economy and home to the world's largest population (1,415,045,928), has a national debt ratio of just 51.21% of its GDP. Germany, as Europe's largest economy, also has a relatively low national debt ratio at 59.81%. Hong Kong, a major global financial center, has the lowest national debt in the world, at just 0.05% of its GDP. This is followed by the tiny Kingdom of Brunei with a population of just 434,076 and a national debt of 2.49% of its GDP

IMF data from the April 2018 IMF World Economic Outlook database.