According to a study carried out by the Economist Intelligence Unit, the most expensive city in the world is Singapore, with an overall cost of living 16% higher than in New York. The second one is Zurich. The cheapest cities are Lusaka, Bangalore, Karachi, Mumbai, Karachi, and Chennai, however, the price of bread in Caracas is almost the same as in Singapore ($3.36 in Caracas vs 3.4$ in Singapore).
The Worldwide Cost of Living (WCOL) is a twice-yearly Economist Intelligence Unit survey that compares more than 400 individual prices across 160 products and services. These include food, drink, clothing, household supplies and personal care items, home rents, transport, utility bills, private schools, domestic help and recreational costs. The survey designed to help human resources and finance managers calculate cost-of-living allowances and build compensation packages for expatriates and business travelers. The survey incorporates easy-to-understand comparative cost-of-living indices between cities.
Source: https://knoema.com/lkzuurc/eiu-worldwide-cost-of-living-report-2016