Examples of Oceans and Seas

From a scientific point of view, there is only one ocean, the "World Ocean," covering 71% of the earth's surface, but everyday speech goes much further than that. At first glance, it may be hard to know what's the difference between oceans and seas. Before we dive into some examples of oceans and seas, let's clear up how you can tell the difference between the two.

Examples of Oceans and Seas Examples of Oceans and Seas

The Difference Between Oceans and Seas

There are three main factors that separate seas and oceans: area, depth, and marine life. Let's briefly discuss these differentiators.


Area is measured in square miles (or kilometers). Oceans will always be larger than seas. Take the Pacific Ocean, for example. It's the largest ocean in the world, covering 60,060,700 square miles. Compare that to the largest sea, the Mediterranean Sea, which covers 1,144,800 square miles.


The next factor is depth. Oceans are also deeper than seas. The Pacific Ocean has a maximum depth of about 35,839 feet. As for the deepest sea, the Caribbean Sea is approximately 22,788 feet deep.

Marine Life

Finally, marine life separates these bodies of water. This is where seas take the lead. Seas tend to have a greater variety of marine life than oceans. This is because they're shallower and allow more sunlight to penetrate. This promotes photosynthesis, which allows the plants and animals to thrive.

List of Oceans

Believe it or not, it's difficult to compile a list of oceans and seas. It's not like listing all the countries in the world. While the scientific definition only provides for the single World Ocean, geographers tend to divide it into five bodies of water.

Here they are, in size order, from largest to smallest:



The Pacific Ocean

60,060,700 square miles

The Atlantic Ocean

29,637,900 square miles

The Indian Ocean

26,469,900 square miles

The Southern Ocean

7,848,300 square miles

The Arctic Ocean

5,427,000 square miles

The Largest Seas

There are many more seas of the world, around 90 depending on strict you are on the definition of a sea. Seas can be compared to large lake-like bodies of water that are at least partially enclosed by land. The only difference is that seas are made of saltwater. Sometimes, seas are attached to oceans, but they don't have to be.

In the examples below, these large seas do happen to be connected to oceans. While this seas of the world list isn't all-encompassing, it does include the world's 10 largest seas, in order from largest to smallest:



Connected Ocean

The Mediterranean Sea

1,144,800 square miles

Atlantic Ocean

The Caribbean Sea

1,049,500 square miles

Atlantic Ocean

The South China Sea

895,400 square miles

Pacific Ocean

The Bering Sea

884,900 square miles

Pacific Ocean

The Gulf of Mexico

615,000 square miles

Atlantic Ocean

The Sea of Okhotsk

613,800 square miles

Pacific Ocean

The East China Sea

482,300 square miles

Pacific Ocean

Hudson Bay

475,800 square miles

Arctic Ocean

The Sea of Japan

389,100 square miles

Pacific Ocean

Andaman Sea

308,000 square miles

Indian Ocean


The Seven Seas

Have you ever heard or read the phrase "sailing the Seven Seas" in a book? Strangely enough, this is an ancient phrase that refers to the five oceans. Throughout history, "Seven Seas" has been referenced in Hindu, Chinese, Persian, Roman, and other texts. Typically, these bodies of water paved the way for trading routes, or simply represented exotic or foreign entities.

Technically speaking, the seven seas constitute the five oceans. So, why the number seven? Throughout history and lore, it's held cultural, historical, and religious significance for many different cultures. There's the "lucky number seven," the "seven deadly sins," and seven chakras, to name a few.

The best way to make literal sense of this title is to consider that the five oceans may have been described according to their cardinal points: north and south. This would then make the Seven Seas:

  • The North Pacific Ocean
  • The South Pacific Ocean
  • The North Atlantic Ocean
  • The South Atlantic Ocean
  • The Indian Ocean
  • The Arctic Ocean
  • The Southern Ocean (The Antarctic Ocean)

Sail the Seas

So, why not sail the seas today? Can you believe land only covers 29% of the earth's surface? That's a lot of water to explore! If you have a love for oceanography, or anything science related, be sure to familiarize yourself with the scientific method. Possessing the ability to turn one of your hypotheses into a proven theory could make you a science star! Until then, happy exploring. If you just love water, explore words to describe water. You can also explore land surrounded by water with archipelago examples.