The next cheapest are Malaysia, Russia, Portugal and Indonesia. At the other end of the scale Japan, The Netherlands, Qatar and Finland rank before the UAE as the most expensive.
For full details see Kiwi.com's landing page here.
To calculate the rankings, Kiwi.com analysed an average price of domestic and international flights on a low cost and a legacy airline from each of the countries.
Domestic flights were calculated by finding an average of flight costs from the country's capital to up to five major cities within the country (where available), or a major city in a neighbouring country where no domestic flights were available, whilst international costs were calculated from the capital of each country to up to five international hubs within the same continent.
All flights were checked for the same dates of travel (or neighbouring dates where necessary) on- and off-season, taking into account the same destinations and travel scheduling.
"The Aviation Price Index is a fascinating guide to the costs of air travel around the globe," said Kiwi.com's chief executive Oliver Dlouhý.
India offered the least expensive domestic flights on both low cost and legacy airlines, at $2.27 and $2.67 respectively per 100km of travel.
China offered the least expensive international flights on both low cost and legacy airlines, at $1.22 and $2.84 respectively per 100km of travel.
United Arab Emirates offered the most expensive domestic flights on both low cost and legacy airlines, at $181.38 and $202.36 respectively per 100km of travel.
Canada offered the most expensive international flights on both low cost and legacy airlines, at $43.70 and $94.66 respectively per 100km of travel.
