What order should you watch One Piece in?
The series order is simply itself: East Blue through the Final Saga in broadcast sequence, because One Piece is one continuous voyage and its arcs hand off directly, often mid-scene. The real questions are films, specials, and versions. The early films are side stories that assume only their era's cast; from Strong World (2009) onward the films were made with Oda's direct involvement in escalating degrees and reward placement near their contemporary arcs, as the Library's movies page details film by film.
The version question is newer. The Fish-Man Island Saga's remastered re-edit in 2024, which compressed 57 episodes into 21 with redrawn and recolored footage, and the announced Wit Studio remake The One Piece, covered in the Library's Wit page, give new viewers alternate entries for the early seas. The Library's guidance: the original series remains the reference text; the re-edits are excellent abridgments for the arcs they cover, and the remake, when it arrives, will be an interpretation to watch after, or instead of, at the viewer's risk tolerance for an unfinished retelling.
Shortcuts exist and should be taken honestly. Episode of East Blue and the other Episode of specials compress their arcs into feature length competently; the Log Collection structure supports arc-by-arc viewing; and the manga is always the fastest complete route, roughly a third of the time of the anime for the same story. What the Library advises against is episode-skip lists that remove canon scenes inside mixed episodes; use the filler page for arcs, not scissors for episodes.
The live-action series sits outside the order entirely: an adaptation of East Blue (and beyond, in later seasons) for a different medium, best watched as its own telling once the original's corresponding arcs are known, where its changes read as choices rather than spoilers.
