Big Mac became the product name used for McDonald's famous burger-themed index.
The Big Mac Index was created by The Economist in 1986 as an informal way to discuss purchasing-power parity. It compares the price of a Big Mac in different countries and uses the sandwich as a common consumer product available across many markets. The index is not an official economic statistic, but it offers an accessible illustration of currency valuation and price differences.
The choice of the Big Mac reflects the sandwich's international presence and standardized branding. A comparable product sold in many countries makes the comparison easier to understand, even though recipes, taxes, wages, rents, and local operating costs vary.
The index is sometimes described as a precise measure of whether a currency is correctly valued. It is better understood as a simple teaching tool. Its name comes from the sandwich, not from McDonald's corporate financial reporting or a restaurant loyalty program.