The world’s largest deserts
This reference ranks the largest deserts on Earth by area, from the polar ice deserts of Antarctica and the Arctic down through the great hot deserts and on to the cold and coastal deserts. Each entry shows the approximate area in square kilometres, the climate type, and the countries or regions it spans. Filter by name, type, or location to focus the list.
What makes something a desert?
The intuitive picture of a desert — burning sand dunes, camels, scorching heat — fits only one of the four main desert types. The scientific definition has nothing to do with temperature: a desert is any region that receives less than roughly 250 mm of precipitation per year. By that measure, the two largest deserts on Earth are frozen.
This matters for reading the table. Antarctica alone covers about 14 million km², making it the largest desert by a wide margin. The Sahara, the largest hot desert at roughly 9.2 million km², comes third. If you are looking for the list that matches the school-geography picture, filter to the hot subtropical type.
The four desert types
| Type | How it forms | Examples |
|---|---|---|
| Polar | Extremely cold air holds little moisture; precipitation falls as tiny ice crystals | Antarctic, Arctic |
| Hot subtropical | Trade-wind circulation subsides dry air over latitudes 20–30° N/S | Sahara, Arabian, Australian |
| Cold winter | Deep continental interiors far from moist ocean air; cold in winter, hot in summer | Gobi, Patagonian, Great Basin |
| Coastal | Cold offshore currents chill onshore air, wringing out moisture before it arrives | Atacama, Namib |
Reading the size figures
Desert boundaries are drawn where aridity criteria are met, and those edges shift with climate patterns — a wetter decade can temporarily shrink a desert margin. Different scientific authorities also draw the boundary slightly differently. The areas in this table are widely cited representative values, rounded to the nearest round figure, and intended for comparison rather than precise land surveying.
For the Sahara specifically, estimates in the literature range from roughly 8.5 to over 9.5 million km² depending on how the semi-arid fringe is treated. The Patagonian and Great Basin deserts vary similarly depending on whether adjacent steppe is included.
Notes and caveats
- Polar deserts dwarf hot deserts: Antarctica alone is bigger than the Sahara and Arabian deserts combined.
- The Atacama is widely regarded as the driest non-polar place on Earth; some measurement stations there have recorded decades without rain.
- Semi-arid steppe and scrubland border several deserts and are sometimes included or excluded depending on the rainfall threshold and the source.
- Areas expand or contract with climate, so figures here reflect a historical typical extent rather than any single year’s measurement.