SINGAPORE is now the sixth most expensive city to live in, a survey by the business intelligence arm of the Economist magazine shows.

Singapore moved up three places from last year's ninth position to rank behind Melbourne, Oslo, Sydney, Osaka and Tokyo as the most expensive cities in the world.

It is also the third most expensive Asian city to live in, outside of the Japanese cities of Osaka and Tokyo.

The survey used New York as the base and measured the cost of 50,000 individual prices of items.

The survey also said that Singapore was 135 per cent most expensive than New York.

In contrast, Pakistani city of Karachi was at the bottom of the list and ranked as the cheapest city out of 130 in the world.