The 2025 Demon Slayer movie, “Demon Slayer: Kimetsu no Yaiba – The Movie: Infinity Castle,” has a runtime of 155 minutes, which is about 2 hours and 35 minutes.

Quick Scoop

  • Official runtime: 155 minutes (2 hr 35 min).
  • This length is confirmed by box office and movie data sites that list the running time as 155 minutes.
  • Fans on anime forums also widely discuss and repeat the 155‑minute length for the Infinity Castle movie.

So if you’re planning a watch, blocking out around 3 hours including trailers and credits is a safe bet.

TL;DR: When people ask “how long is the Demon Slayer movie 2025” , they’re usually referring to the Infinity Castle film, which runs 155 minutes (about 2 hours and 35 minutes).

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