It was thought that the "island" has the size of 5,000,000 km². After reading a bit about geography, I'm unsure. My island would be far bigger than even the largest islands on Earth. But it would still be much smaller than the continents on earth. Now I'm undecided. Would the size still be fine for an island or should I call it a continent?

  • $\begingroup$ An island 500 million $km^2$ would be equivalent in area to a sphere some 6308 km in radius and the Earth is only 6371 km in radius on average, so you need a very large planet to fit your island or you've got your units or the number of zeros wrong. $\endgroup$ Jul 21, 2018 at 12:05
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    $\begingroup$ I think 5 million $km^2$ is still continent sized - it's about 65% the size of Australia and I defy anyone not looking for a lot of angry Aussies to call that an island. $\endgroup$ Jul 21, 2018 at 12:13
  • $\begingroup$ @StephenG Spot on, cobber! Anyone calling Australia is a dead dingo. We are happy to call it an island continent. Antarctica and Greenland also qualify as island continents. But plain old continent is still fine. $\endgroup$
    – a4android
    Jul 21, 2018 at 12:47
  • $\begingroup$ What is the official definition to distinguish island and continent? Is there any? I seem to recall from geography class in high-school (decades ago) that it is a continent if it has inland weather patterns that are largely independent of the sea. $\endgroup$
    – Tonny
    Jul 21, 2018 at 15:45
  • $\begingroup$ Not my field but Wikipedia suggest the difference is in geology with respect to the the nature of their connection to the tectonic plate underneath. That still seems a little subject to interpretation. $\endgroup$ Jul 21, 2018 at 17:24

3 Answers 3


Your island simply needs to be part of a big Continental plate You will notice that Greenland is part of the North american plate and therefore an island. But India can be called a sub-Continent because it is on its own plate. The movement of these plates is what typically causes earthquakes. So the African plate is moving with about 1 cm per year towards Europa. Whilst the British isle's are still in the same spot in relation to mainland Eurasia when a ice age separated them. Even though erosion of the coast might suggest otherwise.

So if you need a large island have there be a larger piece of land than you island nearby. And the sea or strait between them should have no underwater Vulcan's or earthquakes near the coastal regions.

So it all depends on whether you care about having small volcanic island's between your island/continent and its mainland or not. Most people wont care much as long as there does exist a bigger piece of land mass close by. or lots of same sized big islands.


There is a continuum between an islet (a tiny island) and Eurasia (the largest continent.)

There is no scientific distinction that makes Europe and Asia separate continents and makes Australia a continent and Greenland not. (Geology speaks of "continents", but the definition is different from the geographical one.)

The geographical term is an arbitrary distinction which is never-the-less useful in communication. So if you want to stress how large it is call it a continent, and if you want to stress how isolated and limited it is, call it an island. (Whatever you do, don't call it a continent and then call larger land masses islands or call it an island and then call smaller land masses continents.)

It's all about communication, so choose your word to communicate what you want to communicate.


It's still a continent. A good borderline is 1/4 the size of Australia


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