The Singapore passport has been ranked the world's second-most powerful, climbing two places in the annual Henley Passport Index released yesterday.

According to the ranking compiled by global citizenship and residence advisory firm Henley & Partners, Singapore passport holders can travel to 176 countries visa-free.

In the top spot is Germany, whose passport holders can travel to 177 countries without a visa.

Coming in joint third are Denmark, Finland, France, Italy, Japan, Norway, Sweden and Britain, whose passports allow visa-free travel to 175 countries.

The Singapore passport also retained its top spot as the most powerful in the region, with Malaysia coming in second.

According to its website, the Henley Passport Index is formulated based on data from the International Air Transport Association, which maintains the world's largest database of travel information.

Additional research was also used to supplement the index.

Henley & Partners specialises in residence and citizenship planning and updates the passport index throughout the year.

The index takes into account 219 countries and territories.

Overall, 143 countries improved their ranking on the index over the past year, while seven countries saw their visa-free access reduced.

In a separate ranking last October, the Singapore passport was ranked the most powerful in the world by Arton Capital, with a visa-free score of 159. The firm's index ranked Germany second, with a score of 158, and Sweden and South Korea third with a score of 157.

However, by last month, the index put Germany back in top spot.