Japan vs Mauritania

Mauritania is 2.73 times larger than Japan. Japan would fit into Mauritania about 2.7 times.

JapanMauritaniaJapan moved onto Mauritania · Equal-area projection
0.37×
Japan is 0.37× the area of Mauritania. Put the other way, Mauritania is 2.73× the size of Japan.
JapanMauritania
Area377,972 km²1,030,700 km²
Population123,366,7345,315,065
Density326 / km²5.2 / km²
CapitalTokyoNouakchott
RegionEastern AsiaWestern Africa
CoastlineHas a coastHas a coast
Neighbours04

Why the map you grew up with disagrees

On a Mercator map, area grows with distance from the equator. Japan sits at about 37°N and is stretched to 1.59× its true area; Mauritania at 20° N is stretched to 1.14×. Here the two are distorted about the same amount, so Mercator gets this pair roughly right. The figure above uses the Equal Earth projection, where every square kilometre is drawn the same size.

Questions about this pair

Is Japan bigger than Mauritania?
No. Japan is 2.73 times smaller than Mauritania. Japan covers 377,972 km² and Mauritania covers 1,030,700 km².
How many times does Japan fit into Mauritania?
About 2.7 times: Mauritania has 2.73× the area of Japan.
Why do Japan and Mauritania look different on Google Maps?
Web maps use the Mercator projection, which stretches area with distance from the equator. Japan is drawn about 1.59× its true area there and Mauritania about 1.14×. For this pair the distortion is similar, so Mercator gets the comparison roughly right. Kartavera uses Equal Earth, where every square kilometre is drawn the same size.
Which has more people, Japan or Mauritania?
Japan: 123,366,734 people against 5,315,065. Density: Japan 326 per km², Mauritania 5.2 per km².