In the latest real-time update of the Henley Passport Index, the podium is topped by a trio of Asian countries.
Nigeria was 94 in 2018 but has risen by three spots as its passport can take its holder into 47 countries without a visa.
Despite Irish passport holders being able to access eight more countries visa-free compared with last year, it fell by two places from last year's index, when citizens could go to the fifth most countries.
European countries also performed favourably, with European Union member states (along with Norway and the US) filling in the places behind the top three nations - although the United Kingdom continues to drop down the rankings, along with the US.More news: Meghan Markle could possibly return to Suits
The Henley Passport Index said that sixth place is a significant fall for the United Kingdom and U.S. passports, because both held top spot in 2015. The island nation doesn't share the top spot with any other countries.
South Koreans have one of the strongest passports in the world, . because Korean passports don't require a prior visa to travel to most countries.
The South Korean passport was third in the previous index, released in October a year ago, and rose a place in the ranking due to a new visa-on-arrival agreement with India.
Just behind them are Denmark, Finland, Italy, and Sweden on 187, followed by Luxembourg and Spanish passports which can be used to travel to 186 countries.
The Henley Passport Index is based on data provided by the International Air Transport Authority (IATA) and covers 199 passports and 227 travel destinations.More news: Kei Nishikori rolls into Brisbane final
The "continued dominance" of Asian countries in the passport index reflects the "extraordinary effect that global mobility and migration has had on the region", said Henley & Partners, a citizenship advisory firm.
According to Cummings, over the past year, several African countries - notably Angola, Ethiopia, Kenya, Namibia and Senegal - relaxed visa requirements, with the intention of enhancing trade, co-operation, and security. Germany and France remain in third place going into 2019, with a visa-free/visa-on-arrival score of 188.
At the far end of the table, Iraq and Afghanistan remain at the bottom of the rankings, with access to just 30 visa-free destinations.
China's steady ascent up the rankings is a clear demonstration of this.More news: Toni Kroos facing one month out with muscle injury