Best selling albums

This is a list of the world's best-selling albums of recorded music. The criteria are that the figure must have been published by a reliable source and the album must have sold at least 20 million copies worldwide. This list can contain any types of albums, including studio albums, greatest hits, compilations, various artists, soundtracks and remixes. The figures given do not take into account the resale of used albums.

All albums included on this list have their available claimed figures supported by at least 30% in certified copies. The percentage amount of certified sales needed increases the newer the album is, so albums released before 1975 are only expected to have their claimed figures supported by at least 30% in certified copies. However, newer albums, such as 21 and Come Away with Me, are expected to have their claimed figures supported by at least 70% in certified copies. Certified copies are sourced from available online databases of local music industry associations. This is the reason why albums that would otherwise make the list, such as The Sound of Music, Parallel Lines, In-A-Gadda-Da-Vida, Spirits Having Flown, Janet, Believe, Private Dancer, Human Clay, Laundry Service and Back to Black, have not been included.

As a result of the methodology that the American and Canadian certification-awarding bodies (the RIAA and Music Canada respectively) use, each disc in a multi-disc set is counted as one unit toward certification, leading to many double albums on the list—such as Pink Floyd's The Wall and the Beatles' The Beatles—being certified with a number double the number of copies sold there. Such albums have the certifications for the number of copies (not discs) shipped indicated. Conversely, the American certification level for double albums that fit onto one compact disc, such as the Saturday Night Fever soundtrack reflect the actual number of copies sold.

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