This is a ranking system according to the information we have seen thus far...
I maybe forgetting people so please remind me if I do. Secondly if you disagree with anyone's ranking please give me a detailed post why so. I'll change it or respond in kind with a reason of my own why I disagree...
I didn't put in people such as Van Augur or the rest of the BB crew (with the exception of Shiryuu) because we have yet to see them fight seriously...
Please also note that people within certain levels can vary in strength & people 1 level above or below can fight with subsequent ranks. For example someone from rank 6 can beat someone from rank 7.
This ranking is to show overall 'Power' & does not account for things like 'Luffy's In-human Will'...
People may move up or down & if necessary we can add .5 ranks & more to show the varying degrees of strength within each rank.
Please try not to flame me if you disagree and explain why you think I'm wrong (if you do.). I did not make this thread to cause arguments or the like and I will listen to any and all opinions fairly.
I also understand that their are things within One Piece that we can't as of yet predict or judge. I'm simply trying to give a rough estimate. I would like to work with you all so that we can have the most accurate rankings on characters. To help further or One Piece discussions & Theories!
Thank You. 
Order 0.5-10. 0.5 being weakest 10 being strongest.
Deceased or No On Panel Fights = Name
Color Code:
Whitebeard Pirates = Green
Roger Pirates = Teal
Strawhat Pirates = Dark Orange
Shichibukai = Magenta
Supernovas = Gray
Revolutionaries = Sienna
Marines/World Government = Purple
Blackbeard Pirates = Dark Slate Blue
Redhair Pirates = Dark Red
No Current Affiliation = Black
Rankings:
Level 10: WhiteBeard, Gol D. Roger
Level 9.5: Garp & Sengoku
Level 9: Akainu, Kizaru, Aokiji & Shanks
Level 8.5: Marco, Rayleigh
Level 8: Jozu, Mihawk, Kuma(Not Pacifista), Doflamingo, Hancock, Beckman, BlackBeard
Level 7.5: Enel, Magellan, Ace
Level 7: Vice Admirals, Ivankov, Crocodile, Jimbei, Vista, Shiryuu & Sentoumaru
Level 6.5: Smoker, Pacafista, Oars, Inazuma
Level 6: Luffy (Pre-Time Skip), Rob Lucci, T. Law, A. Kidd, B. Hawkins, XDrake, Moria
Level 5: Zoro, Sanji, Killer, J. Bonney
Level 4.5 Bepo, S. Apoo
Level 4: Daz Bones, Brook, Franky, Robin, Urouge, Hina, Hannyabal, Ryuuma, Perona, Absalom
Level 3: Taishigi, Colby, Bon Kurea, Nami, Chopper, Usopp, B. Capone
Level 2: Bellamy & Arlong
Level 1: Duvall, Buggy, Galdino
Level 0.5: Don Kreig, Kuro
Current Version = v.04
Spoiler: Latest Updates
showLatest Updates:
New Rank: 4.5 & 0.5
Added:
Level 6.5:
Inazuma
Oars
Level 6:
Basil Hawkins
XDrake
Level 5:
Killer
Jewelery Bonney
Level 4.5:
Bepo
Scratchman Apoo
Level 4:
Urouge
Hina
Hannyabal
Ryuuma
Perona
Absalom
Level 3:
Bege Capone
Level 0.5:
Don Kreig
Kuro
Spoiler: Future Updates
showFuture Updates:
Post Time Skip Rankings (For all reappearing One Piece characters.)
Fake Strawhats
New Supernova's
Yonkou
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