With Gear 5, Monkey D. Luffy has become one of the strongest characters in One Piece. But still there are people who are stronger than him.
One piece: Speculating on the role of Luffy's Gear 5 in the Upcoming Story Arcs
One Piece: 4 characters that can take on Luffy's Gear Fifth (and 4 that cannot)
I drew what Luffy could look like in Gear 5 (if it happens) : r/OnePiece
Luffy Gear 5th might just be the combination of bouncing and snake man + all forms of advanced haki with a conqueror haki aura around him. Getting close to Shanks level…. What
All Conqueror Haki in One Piece, Ranked
Luffy's Conqueror Haki Timeline: Key Episodes And Turning Points
Every One Piece Haki and Its Subtypes, Explained
How powerful is Luffy with gear 5 and his Toon Force? - Quora
Top 10 Most Powerful Conqueror's Haki Users In One Piece, Ranked
Luffy's Gear 5 is Stronger than Fans Realized and the One Piece Anime Confirms it
Who are the top 3 in each individual type of haki?(speculation) : r/OnePiece
One Piece: Every Sub-type of Haki, Explained