In August 2011,
Tetsuya Nomura expressed desire to release a high definition re-release of the game, though he had yet to confirm such plans. The idea for a high definition re-release preceded plans for
Final Fantasy X re-release, and was a focus for two Square Enix programmers for over a year. In September 2012, Square Enix announced
Kingdom Hearts HD 1.5 Remix for release in Japan on the PlayStation 3. The collection, developed in-house by Square Enix's
1st Production Department, would include both
Kingdom Hearts Final Mix and
Kingdom Hearts Re:Chain of Memories in high definition and Trophy support, as well as non-playable HD event scenes from
Kingdom Hearts 358/2 Days as a way for players to understand the story. The development team experimented with using some character models from
Kingdom Hearts 3D: Dream Drop Distance for
HD 1.5 Remix. The cutscenes from
Kingdom Hearts Final Mix were remastered with Japanese voice overs for both
Chain of Memories and
358/2 Days so that 70% of main story scenes would have full voice acting. In January 2013,
Jesse McCartney, the voice of Roxas, posted a picture on
Instagram of himself in a recording booth, with Roxas seen on a screen in the background, along with the caption, "For all you 'Kingdom Hearts' Fans. Recording the next chapter! #KingdomHearts #Roxas #Gamers." McCartney later deleted the image. In February, Square Enix confirmed the game would release in North America and Europe, later revealing September 2013 releases for North America, In June 2013, Nomura stated that the original game assets for
Kingdom Hearts had been lost some time ago. He explained, "[The game data] was lost, so we had to research, and we had to dig out from the actual game what was available and recreate everything for HD. We had to recreate all the graphics and it was actually not that easy." In July 2017, Nomura spoke on bringing the collection to
Xbox One, saying he did not believe there was much demand for it outside of North America, but felt it could be a possibility after Square Enix completed development on
Kingdom Hearts III. At the X019 event in November 2019,
Shinji Hashimoto and Ichiro Hazama announced that the collection, along with
2.5 and
2.8, would be released on the Xbox One in 2020. The game released on
Windows exclusively via
Epic Games Store on March 30, 2021, and later on
Steam on June 13, 2024, following the expiration of the exclusivity. In October 2021, it was announced that a
cloud version of the game was in development for
Nintendo Switch as part of
Kingdom Hearts HD 1.5 + 2.5 Remix. ==Release==