File formats
CS2 Demo Formats: .dem, .dem.zst & .dem.bz2
The demo content can arrive as a raw .dem file or inside a compressed representation. Compression changes transfer size, not the fact that the underlying asset is a game replay rather than video.
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What each extension means
- .dem is the raw replay file used by CS2 and supported demo tools.
- .dem.zst is a demo compressed with Zstandard.
- .dem.bz2 is a demo compressed with bzip2.
- .mp4 is an encoded video output and cannot be parsed as a match demo.
Upload behavior
Choose the supported demo file you downloaded. n1cetry handles the upload, including supported compressed formats, so you do not need to convert it first.
What stays after upload
- A previously analyzed demo may open faster while its local result is still available.
- The demo is kept only while it is needed to create videos.
- If the original demo is no longer available, uploading it again is acceptable.
- Finished videos remain in your library until you delete them.
Frequently asked questions
Should I extract a .dem.bz2 before uploading?
It is not required when the upload flow supports that compressed demo format. Keeping it compressed can save transfer time.
Can I rename a video to .dem?
No. Renaming the extension does not convert encoded video into game replay data.