Metallica's The Black Album had sold 31 million copies worldwide on physical media according to its album article.
That total reflects the record's extraordinary long-term reach across formats such as CDs, cassettes, and vinyl. Its commercial impact was not limited to the initial 1991 release: the album continued selling for decades and remained a major catalog title.
The figure can be confused with other milestones. The album had sold 16.4 million copies in the United States by 2016 during the Nielsen SoundScan era, while the Recording Industry Association of America later certified it for 20 million US shipments. Those are different measurements from the worldwide physical-media total.