Yellow Sea is 1.01× the size of Japan

The Yellow Sea (sea) covers about 377,000 km² (146,000 mi²) and Japan (country) about 374,000 km² (144,000 mi²). Below, both outlines are drawn at one scale and centred on each other. The Yellow Sea outline is Natural Earth’s, checked against the published area.

377,000km²Yellow Sea
374,000km²Japan

500 km

Yellow Sea
Japan

What fits

Japan is 99% of the size of Yellow Sea.
Yellow Sea is larger by 3,790 km² (1,460 mi²), which is 1.0% of the area of Japan.
Measured in Belgiums: Yellow Sea is about 12.3, Japan about 12.2.

How they differ

Their centres are about 1,280 km apart.
On a standard web map Japan looks larger than Yellow Sea: Yellow Sea at 36°N is drawn about 1.5× too large and Japan at 37°N about 1.6×, so the map shows Japan as 1.03× the size of Yellow Sea, when Yellow Sea is 1.01× the size of Japan.
Together Yellow Sea and Japan cover 751,000 km², close to the size of Zambia (752,000 km², 0.1% bigger).
The gap between them, 3,790 km², is about the size of Cape Verde (3,930 km²).
Japan's centre is 1.7° of latitude, about 190 km, farther north than Yellow Sea's.
The Yellow Sea is a sea and ranks 16th of the 42 seas on sizeversus by area.
Japan ranks 63rd of 212 countries by area.
Laid out flat, the Yellow Sea stretches about 895 km north to south and 704 km east to west; Japan about 2,270 km by 2,080 km.
Poured over Japan, the 17 km³ that Wikidata records for the Yellow Sea would stand 0.0 m deep.
Wikidata’s published figure of 380,000 km² agrees with our measured 377,000 km², to within 2%.

Who wins on what

Measure	Winner	By
Larger area	Yellow Sea	1.01×
Farther north	Japan	1.7° of latitude

Both against the same yardsticks

Yardstick	Yellow Sea	Japan
Belgium 30,700 km²	12.3×	12.2×
United Kingdom 244,000 km²	1.55×	1.53×
Germany 358,000 km²	1.05×	1.04×
France 548,000 km²	0.69×	0.68×
India 3,151,000 km²	0.12×	0.12×
Brazil 8,473,000 km²	0.04×	0.04×
United States 9,447,000 km²	0.04×	0.04×
Russia 16,980,000 km²	0.02×	0.02×

Each figure is the place's area divided by the yardstick's.

Side by side

	Yellow Sea	Japan
Is a	Seasea on sizeversus	CountryAsia
Area, measured	377,000 km²146,000 mi²	374,000 km²144,000 mi²
Area, published	380,000 km²Wikidata	378,000 km²Wikidata
Rank by area	16th of 42seas	63rd of 212countries
Greatest depth	152 mWikidata	–
Volume	17 km³	–
Latitude range	32°N to 40°N	24°N to 46°N
On the shore	3 on the shore	–

Published figures: Wikidata (CC0). A lake or a sea has no legal boundary: the measured area is that of Natural Earth’s outline, and it is shown beside the published one.

Natural Earth’s outlines of China, South Korea and North Korea lie within 25 km of the outline of the Yellow Sea. That is what its geometry says, and it is not a statement about who owns the water or where any border runs in it.

Similar in size to Yellow Sea

Similar in size to Japan

More comparisons

Sources and method

Outlines: Lakes and seas: Natural Earth 1:10m physical vectors (public domain), kept only where the measured area is within 10% of the published one. Countries and regions: Natural Earth, 1:10m Admin 0 and Admin 1, public domain.
Boundary: De facto, as drawn by Natural Earth. A lake or a sea has no legal boundary of its own; the outline is a cartographic one.
Area: Measured on the WGS84 ellipsoid from the full-detail outlines, shown rounded. The published figure comes from Wikidata (CC0), fetched 2026-11-11, and is shown beside the measured one.
Drawing: Each outline is projected with an equal-area projection centred on its own centroid, so areas stay true and the two can be laid over each other.
Data built: 2026-11-11

Full method