Nominal vs. Real GDP

GDP can be measured in two key ways relevant to international rankings. Nominal GDP (also called GDP at Market Exchange Rate or GDP at Current Prices) converts each country's output into a common currency — typically the US dollar — using prevailing exchange rates. This makes it sensitive to currency fluctuations: if a country's currency weakens, its nominal GDP in dollar terms shrinks even if the domestic economy grows. Real GDP strips out price-level changes (inflation) to measure the actual volume of output, making it the preferred measure for growth rate comparisons. GDP at Purchasing Power Parity (PPP) adjusts for differences in price levels across countries — a rupee buys more in India than a dollar in the US — and is used to compare living standards and economic size more accurately across countries. On a PPP basis, India has already been the world's 3rd-largest economy since 2011, behind China and the USA.