Video format
The RM format
RM is RealNetworks’ streaming video format from the dial-up era. RealNetworks launched RealVideo in 1997; RealPlayer streamed much of the early web’s video.
When to use RM
Convert RM and RMVB files to MP4 so old recordings stay playable.
It is best for nothing today; convert old downloads and archives, and it opens on VLC and RealPlayer; nothing modern supports it.
How to open it: VLC plays most RealMedia files.
| Full name | RealMedia |
|---|---|
| Extensions | .rm, .rmvb, .rv |
| MIME type | application/vnd.rn-realmedia |
| Introduced | 1997 |
| Compression | Lossy |
| Usually contains | RealVideo with RealAudio (Cook) audio |
| Support | Legacy format |
| Typical size | Small, and low quality by modern standards |
Good at
- Very small files for dial-up connections
Not so good at
- Low quality
- Dead ecosystem: no browser, phone or editor plays it
The common mistake
RMVB files use variable bitrate and play at the wrong speed in some tools; converting gives a normal, steady MP4.
Questions
What is an RM file?
RM (RealMedia) is RealNetworks’ streaming video format from the dial-up era. RealNetworks launched RealVideo in 1997; RealPlayer streamed much of the early web’s video.
How do I open an RM file?
VLC plays most RealMedia files.
How do I convert RM to another format?
Pick the target on this page, or open the Video Converter, drop the RM file and choose a format. It converts in your browser, so nothing is uploaded.