James Bay at a glance
- 30 maverage depth
- 27 mmedian depth
- 409 mmaximum depth
- 64,642 km²water area
James Bay is a bay. Inside its outline the GEBCO grid has about 64,642 km² of water, with an average depth of about 30 m (the middle value is 27 m) and a maximum of 409 m, found at 53.24° N, 81.65° W.
Open the map at the deepest cell and tap to read the depth.
How deep is each part of the James Bay?
The bar splits the James Bay's water by depth. Each colour is a depth band, and the shares add up to 100%.
- 0 to 200 m: 99.9%
- 200 to 1,000 m: 0.1%
- 1,000 to 4,000 m: 0%
- 4,000 to 6,000 m: 0%
- below 6,000 m: 0%
Named features near the deepest point: Henrietta Maria Ridge (421 km), Ottawa Ridge (593 km), Hudson Basin (791 km), Churchill Ridge (1,029 km).
The James Bay if sea level dropped
The slider on the map lowers the sea in steps. This table shows how much of the James Bay's water would be land at each step.
| Sea level lowered by | Becomes land | Share of its water |
|---|---|---|
| 10 m | 9,781 km² | 15.1% |
| 20 m | 23,299 km² | 36% |
| 50 m | 54,182 km² | 83.8% |
| 80 m | 63,014 km² | 97.5% |
| 120 m | 64,506 km² | 99.8% |
| 200 m | 64,605 km² | 99.9% |
| 500 m | 64,642 km² | 100% |
| 1,000 m | 64,642 km² | 100% |
| 2,000 m | 64,642 km² | 100% |
| 3,000 m | 64,642 km² | 100% |
| 4,000 m | 64,642 km² | 100% |
| 6,000 m | 64,642 km² | 100% |
A simple bathtub model: it lowers the sea everywhere by the same amount and does not simulate how water would really drain.
Nearby seas
- Hudson Bay average depth about 111 m
- Gulf of Saint Lawrence average depth about 163 m
- Foxe Basin average depth about 77 m
- Labrador Sea average depth about 1,948 m
- Baffin Bay average depth about 943 m
- Salish Sea average depth about 130 m
Nearest by the centre of each outline. All oceans and seas
Frequently asked questions
How deep is the James Bay?
On average about 30 m in the GEBCO grid (the middle value is 27 m). The deepest cell inside its outline is 409 m, at 53.24° N, 81.65° W.
How big is the James Bay?
About 64,642 km² of water inside its Natural Earth outline, counted from the grid cells that are below sea level.
How much of the James Bay would be land if sea level dropped?
With the sea 10 m lower, about 9,781 km² (15.1%) of its water would be land. At 6,000 m lower, 100% would be. This is a simple bathtub model that lowers the sea evenly everywhere.
Data: depths from the GEBCO_2026 grid, statistics worked out inside the Natural Earth outline of the bay. See data sources and licences. The GEBCO Grid should NOT be used for navigation or for any other purpose involving safety at sea.