Where the World's Islands Are: Counting, Measuring and Peopling Every Island in the GSHHG Shoreline

How many islands are there, who has them, and how many people live on them? I count every island in the full-resolution GSHHG shoreline, give each a country from Natural Earth and a population from WorldPop's 2025 estimate at about 1 km, and test how far the count depends on the map. GSHHG draws 181,588 islands: 179,823 at sea, 1,437 in lakes and rivers and 328 around Antarctica. 51.8% are smaller than 0.1 km²; 23,150 are 1 km² or more, 296 are 1,000 km² or more. Below 1 km² the total depends on resolution: the five GSHHG resolutions give 762 to 181,588 islands and Natural Earth 10m gives 9,628, while counts of islands of 1 km² or more agree within 378 across the three finest GSHHG versions. Canada has the most islands on every threshold (4,048 of 1 km² or more). Islands cover 6.6% of the world's land and hold 841 million people, 10.3% of the world's population; Java, Honshu and Great Britain alone hold 38% of them. Among islands of 100 km² or more the most crowded is Xiamen Island (18,787 people per km²); 77 islands of 1,000 km² or more have no one in the population grid. The largest island in a lake on an island is Glover Island in Newfoundland (163 km²). The results depend on decisions made by the shoreline (what is joined, what is split) and on a modelled population, which I set out. Interactive version: https://maps.tristanhotham.com/world-islands/. Data and code: https://github.com/Tristan-Hotham/world-islands. Blog post: https://blog.tristanhotham.com/2026/10/31/world-islands/.