The Passport Index ranks passports according to their "power", defined around how many countries will let you in without a visa. British and American passports share the top spot. Meanwhile, a South Sudanese or Palestinian passport wouldn't get you into a candy store.
Visa Free Score
Passports accumulate points for each visa free country that their holders can visit without a visa, or they can obtain a visa on arrival.
Passport Power Rank
Passports are ranked based on their Visa Free Score. The higher the Visa Free Score, the better the Passport Power Rank.
The country list is based on the 193 UN member countries and 6 territories (Macao, Kosovo, etc.) for a total of 199. Territories annexed to other countries such as Norfolk Island, French Polynesia, etc. are excluded. Data is based on research from publicly available sources, as well as information shared by government agencies.
The best part of the site is the page where you can sort the passport cover images by color.