The first Demon Slayer: Infinity Castle movie (Infinity Castle Chapter 1) has an officially confirmed runtime of 155 minutes, which is 2 hours and 35 minutes, making it one of the longest anime films ever released.

Quick Scoop

  • Official runtime: 155 minutes (2 hours 35 minutes).
  • This is longer than Demon Slayer: Mugen Train, which was about 1 hour 57 minutes.
  • The 155-minute runtime was announced via the official Demon Slayer channels and widely reported by anime and entertainment outlets in mid‑2025.
  • This film is Chapter 1 of a planned Infinity Castle movie trilogy that adapts the final arc of the manga.

What this means for fans

  • Expect a very packed story: early breakdowns and fan discussions suggest the film covers multiple major battles from the Infinity Castle arc rather than just setup.
  • The extended runtime helps avoid rushing key fights and character moments, which was a common concern when the trilogy was first announced.

Forum and trending chatter

Online forums and social spaces are buzzing about a few points:

  1. Many fans are hyped that 155 minutes gives enough space for big battles like Akaza’s fight plus added anime‑original moments.
  2. Others are speculating that if Chapter 1 is already this long, Chapters 2 and 3 might match or even exceed it to fully cover the remaining manga chapters without cuts.

“That’s even longer than the Mugen Train film—impressive! I hope the upcoming installments follow suit, as this would help to accommodate the remaining story across three films, reducing the chances of it feeling hurried.”

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TL;DR: The Demon Slayer: Infinity Castle movie (Chapter 1) will be 155 minutes long, or 2 hours and 35 minutes, and serves as the first part of a three‑film finale trilogy.

Information gathered from public forums or data available on the internet and portrayed here.