More languages are spoken in Melbourne than there are countries in the world, a cacophony of 251 tongues whose voices stretch to all corners of the city.

It is a thoroughly modern metropolis, a changing city where as older European voices begin to trail off, Mandarin's volume grows louder, particularly in the inner city.

It's a city that can be justifiably proud of its linguistic diversity and one whose forefathers might scarcely recognise from the discussions around them. But demographers warn Melbourne's melting-pot status could be at risk as rising house prices force new migrants into concentrated pockets.

Across the city, three in 10 people speak a language other than English when they get home and the variety grows daily as migration reshapes a city and its people. A major analysis carried out by Fairfax Media reveals 200,000 more Melburnians are speaking a language other than English at home than a decade ago.

In 6 per cent of suburbs more than half the population speaks languages other than English at the dinner table.