Japan vs Mongolia

Mongolia is 4.14 times larger than Japan. Japan would fit into Mongolia about 4.1 times.

JapanMongoliaJapan moved onto Mongolia · Equal-area projection
0.24×
Japan is 0.24× the area of Mongolia. Put the other way, Mongolia is 4.14× the size of Japan.
JapanMongolia
Area377,972 km²1,564,116 km²
Population123,366,7343,568,978
Density326 / km²2.3 / km²
CapitalTokyoUlaanbaatar
RegionEastern AsiaEastern Asia
CoastlineHas a coastLandlocked
Neighbours02

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; Mongolia at 47° N is stretched to 2.15×. That difference is why Mongolia looks so much bigger than it is next to Japan. 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 Mongolia?
No. Japan is 4.14 times smaller than Mongolia. Japan covers 377,972 km² and Mongolia covers 1,564,116 km².
How many times does Japan fit into Mongolia?
About 4.1 times: Mongolia has 4.14× the area of Japan.
Why do Japan and Mongolia 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 Mongolia about 2.15×. That is why Mongolia looks so much bigger than it really is next to Japan. Kartavera uses Equal Earth, where every square kilometre is drawn the same size.
Which has more people, Japan or Mongolia?
Japan: 123,366,734 people against 3,568,978. Density: Japan 326 per km², Mongolia 2.3 per km².