How Many Oceans Are There in the World?

Traditionally, four oceans are recognized:

1. Pacific Ocean – Largest (~165.2M km²), separates Americas from Asia/Australia.
2. Atlantic Ocean – Second largest (~106.4M km²), separates Americas from Europe/Africa.
3. Indian Ocean – Third largest (~73.4M km²), between Africa, Asia, Australia.
4. Arctic Ocean – Smallest (~14.06M km²), largely enclosed by land.

Many oceanographers propose a fifth: the Southern (Antarctic) Ocean encircling Antarctica, though this is not yet universally adopted.