Passport rankings refer to lists that evaluate the strength of a country's passport based on the number of destinations its holders can access without a visa or with visa-on-arrival options. These rankings are often published by organizations like the Henley Passport Index or the Passport Index, which analyze data from various countries to determine their global mobility. Countries with higher rankings typically offer their citizens greater travel freedom, allowing them to visit more countries without the need for a visa. For example, passports from countries like Japan and Singapore often rank at the top, while those from countries with more travel restrictions may rank lower.