Which measurement is bigger?
The recorded diameter of Earth is 3.671 times the recorded diameter of The Moon. The selected measurements are 12,756 km and 3,475 km, respectively.
| Object | Metric size | Imperial size | Dimension |
|---|---|---|---|
| Earth | 12,756 km | 7,926.2 mi | diameter |
| The Moon | 3,475 km | 2,159.3 mi | diameter |
What this comparison measures
See Earth’s equatorial diameter beside the rounded lunar diameter in NASA’s Small Worlds table. The distance between them is not shown to scale; this tool compares the widths of the bodies.
Earth: Rounded equatorial diameter; the polar diameter is slightly smaller.
The Moon: Rounded diameter in NASA’s Small Worlds fact sheet.
The drawings use the same physical scale, but are simplified illustrations. They show a selected linear dimension rather than mass, surface area or volume. The space between objects makes the comparison readable and does not represent a real-world separation.
Inspect the sources
Both measurement sources are linked below the interactive board. The individual Earth entry and The Moon entry provide the selected conventions and related objects.
Change either selection to explore another pair. The full size comparison tool also lets you enter a personal height. To practise estimating rather than reading the answer first, try the daily five.