Most successful album ever was Please Hammer Don't Hurt 'Em, diamond status
accroding to wikipedia:
* 1991 - 2Pacalypse Now (Gold)
* 1993 - Strictly 4 My N.I.G.G.A.Z. (Platinum)
* 1994 - Thug Life Vol. 1 (Gold)
* 1995 - Me Against the World (2x Platinum)
* 1996 - All Eyez on Me (9x Platinum)
* 1996 - The Don Killuminati: The 7 Day Theory (7x Platinum)
Posthumous created studio albums
* 1997 - R U Still Down? (Remember Me) (5x Platinum)
* 1999 - Still I Rise (2x Platinum)
* 2001 - Until the End of Time (4x Platinum)
* 2002 - Better Dayz (3x Platinum)
* 2004 - Loyal to the Game (Platinum)
* 2006 - Pac's Life
Other albums
* 1998 - Greatest Hits (9x Platinum)
* 2003 - Tupac: Resurrection (Original Soundtrack) (Platinum)
total >45 millions
Reasonable Doubt
* Released: June 25, 1996
* Chart positions: #23 U.S.
* Last RIAA description: 1x Platinum
* Singles: "Ain't No Nigga (feat. Foxy Brown)/Dead Presidents", "Can't Knock the Hustle (feat. Mary J. Blige)", "Feelin' It", "Brooklyn's Finest (feat. Notorious B.I.G.)
In My Lifetime, Vol. 1
* Released: November 4, 1997
* Chart positions: #3 U.S.
* Last RIAA description: 2x Platinum
* Singles: "The City Is Mine", "Who You Wit", "Wishing on a Star", "Sunshine"
Streets Is Watching
* Released: May 5, 1998
* Chart Positions: #3 U.S.
* Last RIAA Certification: 1x Platinum
* Singles: "It's Alright", "In My Lifetime (Remix)", "Murdergram", "Only A Customer", "Love For Free"
Vol. 2: Hard Knock Life
* Released: September 29, 1998
* Chart positions: #1 U.S.
* Last RIAA description: 5x Platinum
* Singles: "Hard Knock Life (Ghetto Anthem)", "Money, Cash, Hoes", "Can I Get A ...", "Nigga What, Nigga Who (Originator 99)", "Money Ain't a Thing"
Vol. 3: Life and Times of S. Carter
* Released: December 28, 1999
* Chart positions: #1 U.S.
* Last RIAA description: 3x Platinum
* Singles: "Big Pimpin'", "Do It Again (Put Ya Hands Up)", "Snoopy Track", "Things That U Do"
The Dynasty: Roc La Familia
* Released: October 31, 2000
* Chart positions: #1 U.S.
* Last RIAA description: 2x Platinum
* Singles: "I Just Wanna Love U (Give It 2 Me)", "Change the Game", "Guilty Until Proven Innocent"
The Blueprint
* Released: September 11, 2001
* Chart positions: #1 U.S., #30 UK
* Last RIAA description: 2x Platinum
* Singles: "Izzo (H.O.V.A.)", "Girls, Girls, Girls", "Jigga That Nigga", "Song Cry"
Unplugged
* Released: December 18, 2001
* Chart positions: #31 US
* Last RIAA description: 1x Platinum
* Singles: - "Hard Knock Life", "Girls, Girls, Girls", "Big Pimpin'"
The Best of Both Worlds (with R. Kelly)
* Released: May 15, 2002
* Chart positions: #2 U.S., #37 UK
* Last RIAA description: 1x Platinum
* Singles: "Best of Both Worlds", "Take You Home With Me a.k.a. Body", "Honey"
The Blueprint 2: The Gift & the Curse
* Released: November 12, 2002
* Chart positions: #1 U.S., #23 UK
* Last RIAA description: 4x Platinum
* Singles: "'03 Bonnie & Clyde", ""Excuse Me Miss"
The Black Album
* Released: November 14, 2003
* Chart positions: #1 U.S., #34 UK
* Last RIAA description: 4x Platinum
* Singles: "Change Clothes", "Dirt Off Your Shoulder", "Encore", "99 Problems"
Unfinished Business (with R. Kelly)
* Released: October 26, 2004
* Chart positions: #1 U.S., #61 UK
* Last RIAA description: 1x Platinum
* Singles: "Big Chips", "Don't Let Me Die"
Collision Course (with Linkin Park)
* Released: November 30, 2004
* Chart positions: #1 U.S., #15 UK
* Last RIAA description: 3x Platinum
* Singles: "Numb/Encore
total >33 milions
this is not counting worldwide numbers though, where I'm sure Pac sold more, but even these show Pac sold more