Since prehistoric times, cetaceans have been important food sources, but they also have been seen as monsters of the sea, a perception that did not change much during the past centuries. Due to a better understanding of their biology in recent years, the public perception towards cetaceans has been evolving. Various studies have been developed aiming to evaluate the attitude and perception of humans towards cetaceans, but these have been local and focused on specific target groups. Our study aimed to evaluate the attitude of the public towards cetaceans on a wide scale by using an international online questionnaire distributed exclusively on social media. An attitudinal scale proposed by Kellert (1985) on a Likert scale matrix was used with nine statements referring to dolphins and nine referring to whales. Even though specific constraints occur from such types of research (e.g., mostly highly educated and young respondents from developed countries), 5,222 responses were collected from 107 countries in total. While Europe, North America, South America, and Oceania were well represented, the number of answers from Africa and Asia were limited. Our results revealed a shift in the public attitude towards cetaceans, with the majority of people exhibiting a positive attitude following the global trend of a rising appreciation for wildlife. Whaling nations and ex-whaling nations that have continued that practice until recently exhibited a more negative attitude towards cetaceans, revealing the importance of culture, heritage, and memory in shaping attitudes. Finally, we discuss our findings under the light of the culture and history of different countries.