Sea
Bismarck Sea
Natural Earth’s outline of the Bismarck Sea measures about 331,000 km² (128,000 mi²), the 18th largest of the 42 seas on sizeversus, and about the same size as Finland.
- Finland
- Bismarck Sea
The numbers
- 331,000km²Area, measured128,000 mi² · Natural Earth outline
- 361,000km²Area, publishedWikidata · 8.3% above our measure, flagged
- 2,900mGreatest depthWikidata
The area is measured from the outline drawn above, on the WGS84 ellipsoid; the published figure is shown beside it, and a water body is kept only if the two are within 10%. This one is between 5% and 10% apart, so it is flagged and no comparison is built for it automatically.
What the numbers say about the Bismarck Sea
- The Arabian Sea, the largest of the 42 seas ranked on sizeversus, is 12.5× the size of the Bismarck Sea; the Bismarck Sea ranks 18th.
- The Bismarck Sea sits between the Great Barrier Reef (348,000 km²) and the Sulu Sea (326,000 km²) in the ranking.
- Counted as a country, the Bismarck Sea would be larger than 146 of the 212 countries listed on sizeversus and would rank 67th by area, between Finland (333,000 km²) and Vietnam (329,000 km²).
- It is larger than 47 of the 51 US states and districts (the biggest of them is New Mexico, 315,000 km²) and smaller than 4.
- It is larger than 23 of the 31 provinces and regions of China (the biggest of them is Guangxi, 237,000 km²) and smaller than 8.
- The closest US state is New Mexico (315,000 km²): the Bismarck Sea is 1.05× the size of New Mexico.
- Wikidata records a greatest depth of 2,900 m.
- The Bismarck Sea lies at 4°S, close to the equator, where a standard web map (Web Mercator) is nearly true to size: it inflates area by only about 1.0×.
- Laid out flat, the Bismarck Sea stretches about 510 km north to south and 1,190 km east to west.
- Our measured 331,000 km² is 8.3% below Wikidata’s published figure of 361,000 km². This difference is flagged for review: a lake’s outline may include islands or bays that the published figure leaves out, or the water level may differ. The outline is kept because it is within 10%, and this page is not matched automatically to any other.
About the same size as
Countries
On the shore
Natural Earth’s outlines of Papua New Guinea lie within 25 km of the outline of the Bismarck 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.
Where the Bismarck Sea ranks
The Bismarck Sea is the 18th largest of the 42 seas on sizeversus, ranked by measured area.
Share this outline
Sources and method
- Outline
- Natural Earth, 1:10m Marine Areas (geography_marine_polys), public domain (Marine Areas (geography_marine_polys)). Natural Earth draws marine areas for labels and cuts them at named sub-areas; the outline is kept because its area matches the published one.
- Boundary
- A lake or a sea has no legal boundary of its own. The outline is a cartographic one, and the page says so by showing the measured area beside the published one.
- Area basis
- Measured outline: computed on the WGS84 ellipsoid from the full-detail outline and shown rounded. Published figure: Wikidata (CC0), fetched 2026-11-11. An outline is kept within 10% of the published figure and matched to other places automatically within 5%.
- Depth, volume, height
- As recorded in Wikidata; a volume that cannot be right for the area and depth is left out.
- Shore
- Countries whose Natural Earth outline contains or comes close to the water's outline; computed, not a statement of ownership.
- Drawing
- Each outline is projected with an equal-area projection centred on its own centroid, so areas stay true and two can be laid over each other.
- Data built
- 2026-11-11