The world’s most crowded countries, and the emptiest

Population density is population divided by area, and nothing more complicated than that. It is also one of the more misleading simple numbers in geography, because a single figure for an entire country can hide almost everything interesting about how people in it actually live.

The most crowded sovereign states

Monaco is the extreme case: a population in the tens of thousands packed into about two square kilometres, giving a density in the range of 19,000 people per square kilometre — entirely urban, with nowhere in the country that is not city. Singapore is the clearest case at real scale: a single city-state of around six million people in under 750 square kilometres, with a density in the thousands per square kilometre and essentially no rural land left at all. Bahrain and a handful of other small, heavily urbanised states sit in the same range.

What these have in common is not wealth or poverty — Monaco and Singapore are both prosperous, but plenty of dense places are not — it is simply that none of them has much spare land. A small area with any significant population will produce a high density almost automatically.

The emptiest

Mongolia holds the opposite record among sovereign states not covered mostly by ice: roughly two people per square kilometre, across a country larger than Western Europe. Namibia sits in similar territory, much of it desert. Australia is the case people find most surprising — a developed, urbanised country with a national density among the lowest in the world, because its 26 million people are overwhelmingly concentrated in a handful of coastal cities and the interior is close to empty.

Why "empty" countries can still have crowded cities

This is the real trap in reading a national density figure: it is an average over land that is rarely used evenly. Australia's national density is low; Sydney's is not. Canada's national density is one of the lowest among large countries, and the great majority of Canadians live within a couple of hundred kilometres of the US border — most of the country's land mass holds almost nobody.

The reverse happens too. Bangladesh has one of the highest national densities of any country of real size, and unlike Monaco or Singapore it is not one city — it is a densely farmed river delta, with people spread fairly evenly across agricultural land rather than concentrated in a capital. The same density figure describes two completely different ways of living.

Area can distort it in the other direction

Russia has a national density that looks low, which obscures that most Russians live in the western, European part of the country; Siberia is enormous and nearly empty, and it is doing almost all of the work of pulling the national average down. A country's total area is not evidence of how much of it people actually occupy.

What density is actually useful for

Despite the caveats, density is a genuinely useful shorthand for one thing: how much pressure there is on land, housing and infrastructure in a given area, which is exactly why planners use it even knowing it averages over a lot of local variation. It is a starting question, not a finished answer — the follow-up question, always, is whether the population is spread out or concentrated, and that is the part a single number cannot tell you.

If you want to get a feel for which countries are large and which are populous — two different rankings that density connects — the largest countries list and the country quiz are the fastest way to separate the two in your own head.