Key facts
- 10,927 m is the deepest point in the ocean, in Challenger Deep.
- 4,085 m is the average depth of the oceans.
- 71% of the Earth's surface is below sea level.
- 4,315 m is the average depth of the Pacific Ocean, the deepest ocean on average.
- 2,306 m is the average depth of the Arctic Ocean, the shallowest ocean on average.
- 11 ocean trenches are deeper than anywhere in the Atlantic Ocean.
- 950 named undersea features are on the map.
- 44.2% of those features are seamounts, the most common type.
- 139.1 million km² is the area of the Pacific Ocean, the largest ocean.
- 21.7 million km² of seabed would become land if the sea fell to its Ice Age low.
Every number below is worked out by a script from the GEBCO seafloor grid and rebuilt whenever the data is updated, so nothing is typed in by hand. Each fact has its own link and a button to copy it with a citation. To explore the seabed yourself, open the ocean floor map and tap anywhere for the depth.
How deep is the ocean?
On this site's GEBCO grid the five oceans average about 4,085 m deep, counting each ocean in proportion to its area. The Pacific Ocean is the deepest on average at 4,315 m, and the Arctic Ocean is the shallowest at 2,306 m. The deepest single point is far below any average: 10,927 m.
Source: GEBCO_2026 grid, averaged over the sea cells inside each Natural Earth outline.
Show the numbers
| Pacific Ocean | 4,315 |
|---|---|
| Indian Ocean | 4,036 |
| Atlantic Ocean | 3,883 |
| Southern Ocean | 3,756 |
| Arctic Ocean | 2,306 |
Average depth
4,085 m is the average depth of the five oceans together, with each ocean counted in proportion to its area.
An average hides the shape of the seabed: most of it is a flat plain, with a few very deep trenches.
4,315 m is the average depth of the Pacific Ocean, the deepest ocean on average.
4,036 m is the average depth of the Indian Ocean.
3,883 m is the average depth of the Atlantic Ocean.
3,756 m is the average depth of the Southern Ocean.
2,306 m is the average depth of the Arctic Ocean, the shallowest ocean on average.
Much of the Arctic Ocean is a shallow shelf, which pulls its average down.
How much of Earth is under the sea
71% of the Earth's surface is below sea level in the grid.
This counts every grid cell below sea level, including a few inland basins and lake floors.
362 million km² of the Earth lies below sea level in the grid.
147.9 million km² of the Earth lies above sea level in the grid.
Ice-covered land is measured at the ice surface.
510.1 million km² is the Earth's total surface area, the sum of the land and sea cells in the grid.
What is the deepest point in the ocean?
The deepest point on this site's grid is Challenger Deep in the Mariana Trench, 10,927 m below sea level, at 11.37° N, 142.60° E in the western Pacific. The single deepest grid cell reads 10,931 m. Both come from a gridded model, so they can differ from the figure a survey ship reports for the same spot.
Source: GEBCO_2026 grid. Each trench shows the deepest cell found near its listed Wikidata point.
Show the numbers
| Mariana Trench | 10,931 |
|---|---|
| Tonga Trench | 10,755 |
| Philippine Trench | 10,090 |
| Kermadec Trench | 10,050 |
| Yap Trench | 9,918 |
| Izu-Ogasawara Trench | 9,841 |
| Kuril–Kamchatka Trench | 9,595 |
| Sangihe Trench | 9,595 |
| South Solomon Trench | 9,142 |
| New Britain Trench | 8,949 |
The deepest points
10,927 m is the depth of the deepest point in the grid, in Challenger Deep.
A grid value is an average over a patch of seabed, not one sounding, so it is not the exact figure a ship would measure.
11.37° N, 142.60° E is the position of that deepest point.
A grid cell covers a patch of seabed, so this is the centre of that patch, not a pin.
10,931 m is the single deepest cell anywhere in the grid, in the Mariana Trench.
It sits in a different spot from the Challenger Deep point above, so the two figures differ slightly.
10,927 m is the deepest point of the Pacific Ocean, the ocean with the deepest point of all.
8,824 m is the deepest point of the Atlantic Ocean, the second deepest ocean at its deepest.
5,441 m is the deepest point of the Arctic Ocean, the lowest of the five oceans' deepest points.
Trenches
Mariana Trench is the deepest trench, at 10,931 m.
Tonga Trench is the second deepest trench, at 10,755 m.
Philippine Trench is the third deepest trench, at 10,090 m.
39 oceanic trenches are listed on the map.
The list follows Wikidata, so it is not every trench on Earth.
11 trenches are deeper than the deepest point of the Atlantic Ocean (8,824 m).
Trenches form where one tectonic plate sinks beneath another.
Depth against height
8,627 m is the height of the highest cell in the grid, above sea level.
The highest cell reads lower than the real summit of the mountain because the grid smooths out sharp peaks.
2,300 m is how much further the deepest point is below sea level than the highest cell is above it.
Both ends are smoothed by the grid, so treat the gap as a rough guide.
What undersea features are there?
Source: Wikidata names and types, depths from the GEBCO_2026 grid.
Show the numbers
| Seamounts and guyots | 420 |
|---|---|
| Submarine canyons | 173 |
| Ridges | 112 |
| Ocean basins | 110 |
| Trenches | 39 |
| Fracture zones | 29 |
| Oceanic plateaus | 25 |
| Deeps | 24 |
| Abyssal plains | 18 |
How many of each
950 named undersea features are on the map, with a depth from the grid for each.
The list follows Wikidata, so it leaves out features that Wikidata does not have or places on land.
420 seamounts and guyots are on the map.
112 ridges are on the map.
110 ocean basins are on the map.
173 submarine canyons are on the map.
39 trenches are on the map.
24 deeps are on the map.
Deepest by type
4,748 m is the depth of Schwabenland Canyon, the deepest submarine canyon on the map.
Features other than trenches are measured at their listed point, so these depths are rougher than the trench figures.
5,546 m is the depth of the Angola Basin, the deepest ocean basin on the map.
6,118 m is the depth of the Argentine Abyssal Plain, the deepest abyssal plain on the map.
6,414 m is how far below the surface the summit of South Chamorro Seamount lies, the deepest-lying summit of any seamount on the map.
A seamount shows the depth of its top, not of the seabed around it.
How is the ocean floor spread by depth?
Source: GEBCO_2026 grid. Shares are the five oceans combined, each weighted by its area.
Show the numbers
| 0 to 200 m | 2.2 |
|---|---|
| 200 to 1,000 m | 2 |
| 1,000 to 4,000 m | 34.8 |
| 4,000 to 6,000 m | 59.9 |
| below 6,000 m | 1.1 |
The depth bands
2.2% of the ocean floor lies between 0 and 200 m.
This band is roughly the continental shelf, the shallowest part of the ocean floor.
2% of the ocean floor lies between 200 and 1,000 m.
34.8% of the ocean floor lies between 1,000 and 4,000 m.
59.9% of the ocean floor lies between 4,000 and 6,000 m.
1.1% of the ocean floor lies below 6,000 m.
The deepest band is a thin sliver of the ocean floor.
Shelf and area
139.1 million km² is the area of the Pacific Ocean, the largest ocean.
Areas come from Natural Earth outlines, and seas inside an ocean outline are counted in it.
5.1 million km² is the area of the Arctic Ocean, the smallest ocean.
Which seas are the deepest?
Source: GEBCO_2026 grid, deepest cell inside each Natural Earth sea outline. The Caspian Sea is a lake and is left out.
Show the numbers
| Philippine Sea | 10,931 |
|---|---|
| Arabian Sea | 9,536 |
| Coral Sea | 9,142 |
| Solomon Sea | 8,949 |
| Caribbean Sea | 8,293 |
| Sargasso Sea | 7,761 |
| Banda Sea | 7,602 |
| Bering Sea | 7,043 |
How many
5 oceans are measured on the map.
71 seas are measured on the map.
The Caspian Sea is called a sea but is a lake, and it is left out of the rankings on this page.
268 oceans, seas, gulfs, bays and straits have depth figures on the map.
Deepest, shallowest and largest
10,931 m is the deepest point of the Philippine Sea, the deepest sea.
Seas sit inside or beside oceans, so a sea can hold part of an ocean trench.
5,394 m is the average depth of the Sargasso Sea, the deepest sea on average.
That is deeper than the average of any of the five oceans. Sea outlines come from Natural Earth, so it says as much about where the lines are drawn as about the sea.
9 m is the average depth of the Sea of Azov, the shallowest sea on average.
Very shallow seas are small, and their grid values are rough.
5.6 million km² is the area of the Philippine Sea, the largest sea.
Seas and gulfs you may know
5,030 m is the deepest point of the Mediterranean Sea, which averages 1,844 m.
78 m is the average depth of the North Sea, and its deepest point is 858 m.
It is shallow because it lies on the continental shelf.
3,886 m is the deepest point of the Gulf of Mexico, which averages 1,583 m.
What if sea level dropped?
If the sea fell by 120 m, about the lowest level of the last Ice Age, 21.7 million km² of seabed would become land, 14.8% of today's land area, and all 10 land bridges on the map would be dry. Drop the sea by 6,000 m and only 1% of today's sea would remain.
Source: GEBCO_2026 grid. A simple bathtub model that lowers the sea everywhere by the same amount.
Small drops and the Ice Age
12 sea level steps are on the map, from 10 m to 6,000 m lower.
2.2 million km² of seabed becomes land if the sea falls by just 10 m, 1.5% of today's land area.
Shallow shelves are so flat that a small fall exposes a large area.
3 land bridges open once the sea falls by 50 m: Doggerland (North Sea), Irish Sea floor and Sundaland (Java Sea).
The bridges are a short list of well-known places, not every land link that opened.
21.7 million km² of seabed becomes land if the sea falls by 120 m, about the Ice Age low.
The real Ice Age coastline also changed because the land itself rose and sank.
94% of today's sea is still sea at that level.
10 of 10 listed land bridges are dry at that level, including Doggerland (North Sea).
Draining the oceans
4,000 m is the fall at which the new land first exceeds all of today's land (115% of it).
The map moves in set steps, so the true tipping point lies between this step and the one before.
1% of today's sea would remain if the sea fell by 6,000 m.
What remains is the trenches and the deepest basins.
358.1 million km² of seabed becomes land at that fall, 244% of today's land area.
147 million km² is the area of land today, not counting lakes, used as the baseline for these shares.
Lakes stay water in the model and inland basins below sea level stay land.
What these numbers mean
A grid value is not a sounding
The grid stores one depth for each small cell of seabed, in whole metres. A cell's depth is an average over that patch, so it is not the exact depth of the deepest spot inside it. Narrow trenches are smoothed, and a survey ship or a submersible can report a different figure for the same place.
Much of the seafloor is estimated
Ships have mapped only part of the ocean floor in detail. Elsewhere the grid is filled in from satellite measurements of the sea surface, which show large shapes well but small ones poorly. The seabed in the grid therefore looks smoother than the real thing.
Averages hide the shape
An average depth blends wide, flat plains with a few very deep trenches. Use the depth bands to see how the floor is spread, and the trench and sea rankings to find the extremes.
Sea level pages are a simple model
The sea level figures lower the water everywhere by the same amount and count only seabed connected to the open ocean. They show where land would appear, not how the water would really drain, and they are not a forecast.
Methodology
Depths and heights come from the GEBCO_2026 Grid, ice-surface elevation, published 22 April 2026. It has one value every 15 arc-seconds, stored in whole metres, and this site uses the ice-surface version of the grid rather than the sub-ice one. Ocean and sea statistics use the grid cells below sea level inside each Natural Earth outline, with each cell weighted by its true area. Seas lie inside or beside the oceans, so their areas overlap and should not be added together.
Undersea feature names, types and positions are from Wikidata, which gives one point per feature. A trench shows the deepest cell found near its point, other features show the grid value at or near it, and a seamount shows the depth of its summit. 950 features are listed and 268 oceans, seas, gulfs, bays and straits are measured. The Caspian Sea is a lake and is left out of the sea rankings.
See data sources and licences for every dataset and how it is used, and the lists behind these figures: undersea features, oceans and seas and sea level steps.
Cite this page
You are welcome to quote any number on this page. Please credit Ocean Floor Map and link to this page, so readers can check the figure and see how it was worked out. Every number has its own link and a Copy citation button.
Need the numbers in a spreadsheet? Download every fact on this page as CSV.
Frequently asked questions
How deep is the ocean on average?
About 4,085 m, counting each of the five oceans in proportion to its area, in the GEBCO grid used here. The Pacific Ocean is the deepest on average (4,315 m) and the Arctic Ocean the shallowest (2,306 m).
What is the deepest point in the ocean?
Challenger Deep, at the southern end of the Mariana Trench in the western Pacific. The grid reads 10,927 m there, and its single deepest cell, in the Mariana Trench, reads 10,931 m. Surveys of the same spot report slightly different figures, so quote any one value as "about".
Why do ocean depth figures differ between sources?
Depth is measured by ships with sonar, or estimated from satellite measurements of the sea surface, and different surveys and different grids give different answers. A grid also stores one value for each cell, so a narrow trench is averaged with the ground beside it. This page uses one grid throughout, so its numbers agree with each other even where they differ from figures quoted elsewhere.
What would happen if sea level dropped?
Shallow shelves would dry out first. A fall of 120 m, about the lowest sea level of the last Ice Age, adds 21.7 million km² of land and opens land bridges such as Doggerland. The 4,000 m step is where the new land first exceeds all of today's land. The sea level pages show every step on a map.
Where do these numbers come from?
Every number on this page is worked out by a script from the GEBCO_2026 Grid, ice-surface elevation, published 22 April 2026, with undersea feature names and positions from Wikidata and ocean and sea outlines from Natural Earth. Nothing is typed in by hand. The data sources page lists every dataset and its licence.
Can I use these facts in my article, homework or presentation?
Yes. Quote any number you like and credit Ocean Floor Map with a link to this page. Each fact has a Copy citation button that copies the sentence with a link to that exact fact, and the whole list can be downloaded as a CSV file. Please also credit the GEBCO grid.