The fin whale (Balaenoptera physalus), also called the finback whale, razorback, or common rorqual, is a marine mammal belonging to the suborder of baleen whales. It is the second longest animal in the world and second largest rorqual after the blue whale, growing to 27.3 metres (89.5 ft) long and weighing nearly 74 tonnes (73 long tons; 82 short tons).
The fin whale is listed on both Appendix I and Appendix II of the Convention on the Conservation of Migratory Species of Wild Animals (CMS). It is listed on Appendix I as this species has been categorized as in danger of extinction throughout all or a significant proportion of its range and CMS Parties strive towards strictly protecting these animals, conserving or restoring the places where they live, mitigating obstacles to migration and controlling other factors that might endanger them.
It is listed on Appendix II as it has an unfavourable conservation status or would benefit significantly from international co-operation organised by tailored agreements. In addition, the fin whale is covered by the Agreement on the Conservation of Cetaceans in the Black Sea, Mediterranean Sea and Contiguous Atlantic Area (ACCOBAMS) and the Memorandum of Understanding for the Conservation of Cetaceans and Their Habitats in the Pacific Islands Region (Pacific Cetaceans MOU).