What codec do I need for this video?
Learn why the extension alone is not enough, how to identify the actual video and audio streams, and what to do once you know them.
Read guideUnderstand what is actually inside a media file, identify the codec a video uses, and decide whether you need extra playback support before installing or converting anything.
A file extension such as .mp4, .mkv, .mov, or .avi identifies a container, but it does not necessarily tell you which video and audio codecs are stored inside. These guides explain the difference and show how to identify the streams before changing your system.
Learn why the extension alone is not enough, how to identify the actual video and audio streams, and what to do once you know them.
Read guideUse the file itself to identify its container, video codec, audio codec, resolution, frame rate, bitrate, channels, and other useful details.
Read guideUnderstand why MKV and MP4 are not codecs, and how H.264, HEVC, AV1, AAC, AC3, and DTS fit inside media containers.
Read guideIf you already know the symptom or Windows error code, use the Video Playback Help hub. It has focused fixes for error 0xc00d36c4, 0xc00d5212, missing HEVC or AV1 support, video with no sound, and MP4, MKV, MOV, or AVI files that will not play.