An “AMC file” is not restricted to one format due to extension reuse, though the version most users encounter is a legacy phone-era video container built for tiny screens and low processing power, often encoded with obsolete codecs that modern players may not support, commonly found as small megabyte files in old backups or media folders and appearing as messy binary data when viewed in Notepad.

Trying VLC is the simplest test; if playback works you’re finished, and if not, MP4 conversion is the go-to solution, with HandBrake helping when it detects the file and FFmpeg succeeding by transcoding to H.264/AAC, but .amc might instead be Acclaim Motion Capture motion data—paired with .asf and appearing as structured text—or a macro/config file for niche automation tools containing XML/JSON or command-like entries, and it shouldn’t be mixed up with the unrelated networking concept AMC.

An “AMC file” commonly belongs to three main buckets, which you can determine by looking at its origin, file size, and appearance in a text editor, with the most frequent being a legacy mobile video container from early phone environments—typically megabyte-sized, originating from MMS or Bluetooth folders or old camera directories, and unreadable in Notepad—and VLC gives a quick answer: if playback works, it’s that type, and if not, converting to MP4 is the recommended fix as newer players may not support its structure or codecs.

The second likely meaning is Acclaim Motion Capture used in animation pipelines, storing motion curves rather than video—commonly tiny compared to media files, usually shipped with an .ASF skeleton, and showing human-readable numeric structures when opened, marking it as mocap, while the third meaning refers to a niche macro or config/project file tied to a specific automation tool, generally small and containing XML/JSON-style settings or command-like entries, so the quick breakdown is: large legacy-phone files mean video, motion-data text with .ASF means mocap, and compact structured text means an app-level macro.

To identify whether your AMC file is video, examine its source, its size, and media-player behavior, since AMC files coming from old phone ecosystems—like backups, MMS downloads, Bluetooth exchanges, or DCIM/media folders—are classic signs of the mobile-video type, and anything in the megabyte range is far more consistent with video than the much smaller mocap or macro/config formats.

One easy check is viewing it in Notepad—if the file is a video container, you’ll see messy binary almost instantly rather than readable text or orderly numbers, and the definitive test is VLC: if VLC plays it, it’s video; if not, you may be dealing with unsupported codecs or an entirely different AMC format, so running it through a converter or FFmpeg is the usual way to see whether any audio/video streams can be detected and turned into MP4.