The burger index has another official name. This is Big Mac PPP. And of course you would like to know what does the Big Mac Index compare? https://fbs.com/blog/what-is-the-big-mac-index-323 First of all, it compares currencies with each other. The idea is that if you compare the value of the Big Mac in each country with the US dollar and calculate the exchange rate of the Big Mac index, you can determine whether the currency is overvalued or undervalued against the dollar.