Toronto's crown as most diverse city in the world is often taken for granted by those who live here, but it's actually quite rare for this title to be given out in any official capacity. The majority of global urban diversity rankings pull together short lists of cities that are the most multicultural, but resist declaring a winner based on statistical shortcomings.

While not part of a major study, BBC Radio has bucked this trend in declaring Toronto the most diverse city in the world just a few weeks after newly elected London mayor Sadiq Khan pronounced his city the bearer of such a title.

The biggest problem with diversity rankings is that they tend to rely too heavily on one unit of measurement, namely the percentage of a population born in a foreign country. Such a yardstick, however, fails to take into account the total range of ethnicities found in a given city and necessarily ignores the presence of second generation immigrants.

For this reason, a city like Dubai ranks at near the top of some diversity ratings with a whopping 83 per cent of its population born in another country. That number doesn't tell the whole story, though. While the percentage of foreign-born residents is very high, the total number of countries from which they derive is quite low.

Toronto's population is made up of 51 per cent of residents born outside of Canada, but is also home to 230 different nationalities, which makes it far more diverse than Dubai. According to the statistical analysis done by the radio show, the second most diverse city in the world is Brussels, followed by a toss up between London, Auckland and Los Angeles.

It's not quite definitive, but this ranking at least confirms what most of us tend to take as a given. When it comes to truly global cities, Toronto takes the cake.

Photo by Honey Agarwell in the blogTO Flickr pool.