- Mediterranean Sea – Approximately 2.5 million square kilometers
- Caribbean Sea – Approximately 2.75 million square kilometers
- South China Sea – Approximately 3.5 million square kilometers
- Bering Sea – Approximately 2.3 million square kilometers
- Gulf of Mexico – Approximately 1.6 million square kilometers
- Sea of Okhotsk – Approximately 1.58 million square kilometers
- East China Sea – Approximately 1.25 million square kilometers
- Hudson Bay – Approximately 1.2 million square kilometers
- Andaman Sea – Approximately 797,700 square kilometers
- North Sea – Approximately 570,000 square kilometers
- Red Sea – Approximately 438,000 square kilometers
- Black Sea – Approximately 436,400 square kilometers
- Caspian Sea – Approximately 371,000 square kilometers
- Sea of Japan – Approximately 978,000 square kilometers
- Arabian Sea – Approximately 3.86 million square kilometers
- Sea of Azov – Approximately 39,000 square kilometers
- Adriatic Sea – Approximately 138,000 square kilometers
- Tyrrhenian Sea – Approximately 275,000 square kilometers
- Ionian Sea – Approximately 160,000 square kilometers
- Aegean Sea – Approximately 214,000 square kilometers
- Sea of Cortez (Gulf of California) – Approximately 160,000 square kilometers
- Baltic Sea – Approximately 377,000 square kilometers
- Gulf of Guinea – Approximately 2.34 million square kilometers
- Gulf of Alaska – Approximately 1.53 million square kilometers
- Sea of Japan – Approximately 978,000 square kilometers
- Gulf of Thailand – Approximately 320,000 square kilometers
- Gulf of Oman – Approximately 903,000 square kilometers
- Gulf of Aden – Approximately 1.12 million square kilometers
- Sea of Marmara – Approximately 11,350 square kilometers
- Sea of Galilee (Lake Tiberias) – Approximately 166 square kilometers
- Coral Sea – Approximately 4.79 million square kilometers
- Sea of Japan (East Sea) – Approximately 978,000 square kilometers
- Sea of Azov – Approximately 39,000 square kilometers
- Sea of Crete – Approximately 45,000 square kilometers
- Sea of Japan (East Sea) – Approximately 978,000 square kilometers