Mount Everest vs Olympus Mons: Size Comparison
Olympus Mons is about 2.5× the size of Mount Everest: it measures 21.9 km (14 mi) tall, while Mount Everest is 8,849 m (5 mi) tall.
Everest is the roof of our world — and on Mars it would be a foothill. Olympus Mons rises about two and a half Everests high, and its base would swallow all of France. Mars's low gravity and lack of tectonic plates let one volcano keep growing for billions of years into something no mountain on Earth could ever become.
Measurements side by side
| Mount Everest | Olympus Mons | Ratio | |
|---|---|---|---|
| Length | 15 km (9 mi) | 600 km (373 mi) | 40× |
| Height | 8,849 m (5 mi) | 21.9 km (14 mi) | 2.5× |
To-scale view
Drawn to true scale from the measurements below.
Cinematic scene generated with AI — for accurate proportions, see the to-scale view above.
How many Mount Everests fit in Olympus Mons?
- 2 Mount Everests placed end to end match one Olympus Mons's height.
Frequently asked questions
- Is Mount Everest bigger than Olympus Mons?
- No. Olympus Mons (21.9 km (14 mi)) is about 2.5× the size of Mount Everest (8,849 m (5 mi)).
- How many Mount Everests fit alongside Olympus Mons?
- Placed end to end, about 2 Mount Everests span the full extent of one Olympus Mons.
Similar comparisons
Sources & measurement notes
Mount Everest: 8,848.86 m above sea level — the official 2020 China–Nepal joint survey figure, the highest point on Earth. The breadth of the visible massif (~15 km) is approximate; unlike buildings, a mountain has no defined footprint.
Olympus Mons: The largest known volcano in the Solar System, on Mars: about 21.9 km high — roughly 2.5× Mount Everest — with a base some 600 km across, about the size of France. Its slopes are so gentle (~5°) that from the base you couldn't see the summit.