The largest archipelago in the world is the Malay Archipelago, a chain of more than 25,000 islands between mainland Southeast Asia and Australia shared by Indonesia, the Philippines, Malaysia, Brunei, Timor-Leste and Papua New Guinea. By land area the Canadian Arctic Archipelago comes second at about 1.4 million km², followed by the Japanese Archipelago, the British Isles and the Philippines.
Counting Islands Versus Measuring Land: Two Different Leaderboards
An archipelago is a group of islands close enough together to be treated as one geographic unit. Ranking them is harder than it sounds, because "largest" can mean two different things.
By land area, which is the more meaningful measure, the leading archipelagos are:
- Malay Archipelago — roughly 2 million km² excluding New Guinea, and closer to 2.8 million km² if New Guinea is included
- Canadian Arctic Archipelago — about 1.4 million km²
- Japanese Archipelago — about 378,000 km²
- British Isles — about 315,000 km²
- Philippine Archipelago — about 300,000 km² (strictly part of the Malay Archipelago, but usually listed on its own)
- New Zealand — about 268,000 km², dominated by the North and South Islands
- Svalbard, Franz Josef Land and the other high-Arctic groups — each far smaller, in the tens of thousands of square kilometres
By number of islands, the list looks completely different. Scandinavian coastlines covered in tiny rocky islets win easily, and a single count can change by thousands depending on the minimum size surveyors decide to include. Throughout this article, island counts come from national mapping agencies, and the caveats on each are real.
The Malay Archipelago and the Line Wallace Drew Through It
The Malay Archipelago stretches roughly 6,000 km from Sumatra in the west to New Guinea in the east, straddling the equator between the Indian and Pacific Oceans. It contains three of the world's six largest islands: New Guinea (about 786,000 km², the second largest), Borneo (about 743,000 km², the third) and Sumatra (about 473,000 km², the sixth). New Guinea is sometimes left out because it sits on the Australian continental shelf and is grouped with Melanesia, which is why totals for the archipelago vary so widely.
The British naturalist Alfred Russel Wallace spent eight years here, from 1854 to 1862, collecting more than 125,000 specimens. His 1869 book The Malay Archipelago gave the region its lasting name in English. Wallace noticed a sharp break in wildlife between Bali and Lombok, islands separated by a strait only 20 to 40 km wide: to the west lived Asian animals such as tigers, monkeys and woodpeckers; to the east, Australasian ones such as cockatoos and marsupials.
That boundary, now called the Wallace Line, follows deep-water channels that stayed flooded even when Ice Age sea levels fell by around 120 metres. The western islands — Sumatra, Java, Borneo and Bali — were then joined to mainland Asia as a landmass called Sundaland, while New Guinea joined Australia as Sahul. Our Malay Archipelago guide covers the region's volcanoes and biodiversity in more depth.
Indonesia and the Philippines: Two Nations With Moving Island Counts
Indonesia is the world's largest archipelagic state, with about 1.9 million km² of land spread across roughly 5,100 km from east to west — wider than the contiguous United States. For decades the government cited 17,508 islands, a figure that included many unnamed and unverified features. When Indonesia submitted named islands to the United Nations in 2017, the verified count was 16,056; later survey updates have reported figures of around 17,000. Java, at about 128,000 km², holds more than half of Indonesia's roughly 280 million people, making it the most populous island on Earth. The geography of Indonesia explains how its islands sit along one of the most active volcanic arcs on the planet.
The Philippines has a similar history of revision. The long-standing figure of 7,107 islands was raised to 7,641 after mapping by the country's national mapping agency, NAMRIA, identified hundreds of previously uncounted islets. Eleven islands, led by Luzon and Mindanao, make up about 94% of the land. The archipelago runs about 1,850 km from north to south and is one of the world's 17 megadiverse countries, with an exceptionally high share of species found nowhere else.
The Canadian Arctic Archipelago: Three of the World's Largest Islands
North of the Canadian mainland lie 36,563 islands covering roughly 1.4 million km², divided between the territories of Nunavut and the Northwest Territories. They include three of the world's ten largest islands:
- Baffin Island — about 507,000 km², the fifth largest island in the world
- Victoria Island — about 217,000 km², the eighth largest
- Ellesmere Island — about 196,000 km², the tenth largest
Almost none of it is populated: fewer than 20,000 people live across the whole archipelago, most of them Inuit living in coastal communities such as Iqaluit, the capital of Nunavut, on Baffin Island. The channels between the islands form the Northwest Passage, the sea route between the Atlantic and Pacific that Roald Amundsen first completed by ship between 1903 and 1906. Canada regards those channels as internal waters; the United States and others consider parts of them an international strait, a dispute that matters more as summer sea ice retreats.
Greenland Versus the Canadian Arctic Archipelago
Next door sits a useful comparison. Greenland is a single island of about 2.17 million km² — larger than the entire Canadian Arctic Archipelago, even though that archipelago contains more than 36,000 islands. Both were shaped by the same forces: ice sheets that loaded the land, fjords carved by glaciers, and a shared position on the North American tectonic plate.
The difference is what the ice did. Greenland remains buried under an ice sheet up to about 3 km thick, and radar surveys show that its weight has pressed much of the central bedrock down to around or below sea level, leaving a basin ringed by coastal mountains. If the ice vanished overnight, seawater could reach parts of that interior before the land had time to rebound. The Canadian archipelago shows what that looks like in practice: it lost most of its ice sheet at the end of the last glaciation, and the sea flooded the lowlands and valleys between its uplands, leaving islands separated by channels. One landscape stayed whole under ice, while its neighbour was cut apart by the ocean. Ellesmere Island is separated from Greenland by Nares Strait, which narrows to only a few tens of kilometres — and in 2022 Canada and Denmark settled their long, good-humoured dispute over tiny Hans Island in that strait by splitting it in two.
Japan and the British Isles: Chains on the Edge of a Continent
The Japanese Archipelago runs about 3,000 km from subarctic Hokkaido to subtropical Okinawa. In 2023 the Geospatial Information Authority of Japan recounted the country's islands using digital mapping and arrived at 14,125, more than double the 6,852 counted in 1987 — not because new islands appeared, but because modern maps resolved coastlines in far greater detail. Four main islands — Honshu, Hokkaido, Kyushu and Shikoku — dominate; Honshu, at about 228,000 km², is the seventh largest island in the world. Japan is a volcanic island arc, formed where the Pacific and Philippine Sea plates subduct beneath the Eurasian and North American plates, which is why it has more than 100 active volcanoes.
The British Isles have a quieter origin. They are continental islands sitting on the European continental shelf, separated from the mainland when rising sea levels flooded Doggerland, the plain beneath today's southern North Sea, roughly 8,000 years ago. The group contains more than 6,000 islands. Great Britain, at about 209,000 km², is the ninth largest island in the world, and Ireland, at about 84,000 km², is the twentieth. The Hebrides, Orkney, Shetland and the Isles of Scilly make up most of the rest.
Sweden, Finland and Norway: Hundreds of Thousands of Skerries
If you rank countries purely by island count, Scandinavia wins by a wide margin. A 2014 count by Statistics Sweden found 267,570 islands, most of them bare granite skerries along the Baltic coast and in lakes. Norway's mapping authority counted around 239,000 islands and islets along its fjord coast. Finland's Archipelago Sea, between Turku and the Åland Islands, contains tens of thousands of islands by itself and is often described as the largest archipelago in the world by number of islands.
These coasts share an origin. During the last Ice Age, ice sheets up to 3 km thick pressed the land down and scraped it into countless knobs of hard rock. As the ice melted, the sea flooded the low ground; the land has been rising ever since through post-glacial rebound — by up to about 8 mm a year near the Gulf of Bothnia — so new islands are still emerging and neighbouring islets gradually join together. Most of them cover less than a hectare, which is why these archipelagos top the count but barely register by area. Once you can tell a volcanic arc from a drowned coastline or a field of glacial skerries, test how many of these island nations you can place in the world geography quiz.