San Francisco Bay at a glance
- 7 maverage depth
- 5 mmedian depth
- 100 mmaximum depth
- 1,074 km²water area
San Francisco Bay is a bay. Inside its outline the GEBCO grid has about 1,074 km² of water, with an average depth of about 7 m (the middle value is 5 m) and a maximum of 100 m, found at 37.81° N, 122.49° W.
Open the map at the deepest cell and tap to read the depth.
How deep is each part of the San Francisco Bay?
The bar splits the San Francisco Bay's water by depth. Each colour is a depth band, and the shares add up to 100%.
- 0 to 200 m: 100%
- 200 to 1,000 m: 0%
- 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: Gumdrop Seamount (95 km), Pioneer Seamount (98 km), Guide Seamount (117 km), Monterey Canyon (129 km).
The San Francisco Bay if sea level dropped
The slider on the map lowers the sea in steps. This table shows how much of the San Francisco Bay's water would be land at each step.
| Sea level lowered by | Becomes land | Share of its water |
|---|---|---|
| 10 m | 856 km² | 79.8% |
| 20 m | 1,033 km² | 96.2% |
| 50 m | 1,065 km² | 99.2% |
| 80 m | 1,074 km² | 100% |
| 120 m | 1,074 km² | 100% |
| 200 m | 1,074 km² | 100% |
| 500 m | 1,074 km² | 100% |
| 1,000 m | 1,074 km² | 100% |
| 2,000 m | 1,074 km² | 100% |
| 3,000 m | 1,074 km² | 100% |
| 4,000 m | 1,074 km² | 100% |
| 6,000 m | 1,074 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
- Salish Sea average depth about 130 m
- Golfo de California average depth about 783 m
- Gulf of Alaska average depth about 1,559 m
- Gulf of Mexico average depth about 1,583 m
- Bahía de Campeche average depth about 921 m
- Hudson Bay average depth about 111 m
Nearest by the centre of each outline. All oceans and seas
Frequently asked questions
How deep is the San Francisco Bay?
On average about 7 m in the GEBCO grid (the middle value is 5 m). The deepest cell inside its outline is 100 m, at 37.81° N, 122.49° W.
How big is the San Francisco Bay?
About 1,074 km² of water inside its Natural Earth outline, counted from the grid cells that are below sea level.
How much of the San Francisco Bay would be land if sea level dropped?
With the sea 10 m lower, about 856 km² (79.8%) 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.