More than 70%
The ocean covers more than 70% of Earth's surface.
A journey beneath the surface
Explore the ocean
From sunlit water to the deep sea, every depth has something to discover.
Ocean facts
Three things to know about our ocean.
About 97%
The ocean contains about 97% of Earth's water.
3,682 meters
The ocean is about 3,682 meters deep on average.
0–200 m
Sunlight zone
This bright upper layer receives enough light for photosynthesis.
Zone source: NOAA Ocean Service
Creature facts
- Shallow reef corals are made of tiny animals called polyps. Algae living inside them use sunlight to make food. Source: NOAA Fisheries
- Clownfish can swim among a sea anemone's stinging tentacles. Source: Smithsonian Ocean
200–1,000 m
Twilight zone
Only a little sunlight reaches this layer. There is not enough light for photosynthesis.
Zone source: NOAA Ocean Service
Creature facts
- Lanternfish have tiny light-producing organs. Many swim toward the surface at night to eat. Source: Woods Hole Oceanographic Institution
- Bristlemouths are small fish with dark skin and glowing dots along their bellies. Source: Woods Hole Oceanographic Institution
Below 1,000 m
Dark ocean
Sunlight does not reach this deep. This dark region includes the midnight zone, the abyss, and ocean trenches.
Zone source: NOAA Ocean Service
Creature facts
- Many female deep-sea anglerfish use a glowing lure to attract prey. Source: NOAA Ocean Exploration
- Vampire squid can venture into this dark zone. They gather drifting bits of food called marine snow. Depth source: Smithsonian Ocean · Food source: Monterey Bay Aquarium
- Dumbo octopus uses large fins to swim through dark water. Some have been found 4,000 meters deep. Source: NOAA Ocean Exploration
- Giant isopod can live as deep as 2,100 meters and scavenges food that sinks to the seafloor. Source: Monterey Bay Aquarium
Ocean quiz
Try to answer each question, then open it to check your guess.
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How much of Earth's surface does the ocean cover?
Show answer
More than 70%. Learn more from NOAA Ocean Service.
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Which ocean zone has enough sunlight for photosynthesis?
Show answer
The sunlight zone. Learn more from NOAA Ocean Service.
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What do many female deep-sea anglerfish use to attract prey?
Show answer
A glowing lure. Learn more from NOAA Ocean Exploration.