.DASH File

The dash file extension is mainly related to the Dynamic Adaptive Streaming over HTTP video file format, also simply known as DASH.

The MPEG-DASH provides a standard specification for multimedia streaming over the Internet. The DASH format is used to transport high quality video in encoded MP4 format on the Internet through own DASH protocol.

A typical dash file stores video content in several bitrates to ensure that the video is playable even with unstable internet connection. However, these files do not contain the audio track, which is saved in different file.

DASH format is meant only for watching, not downloading, so there is currently no way how to make the downloaded fragments working as common media play in media player.

One could also look on these files are temporary files, that are generated on the client side during the playback through supported media player. They contain just fragments of the original video, not the original.

Files with dash file extension can be usually found as video streaming files in Dynamic Adaptive Streaming over HTTP video file format.

How to open:

You can playback DASH video using VLC player with DASH Plugin installed.

How to convert:

It seems that direct conversion from DASH is generally not possible.