Blue (Da Ba Dee)" is a song by Italian music group Eiffel 65. It was first released in October 1998 in Italy and became internationally successful the following year. It is the lead single of their debut album Europop. The song is the group's most popular single, reaching number one in many countries such as Ireland, the United Kingdom, the Netherlands, France, Sweden, Switzerland, New Zealand, Finland, Norway, Australia, Germany and Hungary, as well as reaching number six on the Billboard Hot 100 in the United States.