What is RM File Format?

RM file format

The RealMedia (RM) file format is a multimedia container, which was developed by RealNetworks, an American company based in Seattle, Washington. An RM file has .rm as an extension.

Characteristics and Uses

The RM file format is used for streaming content over the Internet. Streaming is a technology that allows the user to play a file at the same time as it is being downloaded. RM files are used by the Real Media Player software to open files in Windows, Mac and Linux based devices.


A RM file is composed of a series of chunks, each having the following format:

  1. dword chunk type (FOURCC)
  2. dword chunk size, including 8-byte preamble
  3. word chunk version
  4. byte[] chunk payload

The chunk type can be any of the following:

  1. .RMF: RealMedia file header
  2. PROP: File properties
  3. MDPR: Stream properties
  4. CONT: Content description/metadata
  5. DATA: File data
  6. INDX: File index

The first chunk is of .RMF type and contains the number of headers. The PROP chunk contains the general properties of the RM file. The MDPR chunk defines the type of stream and codec used. The CONT chunk contains information about the content of the file, such as title, author, etc. The DATA chunk contains data packets, which are interleaved for each stream. Finally, the INDX chunk contains index entries.

RM files can work with CLV1 – ClearVideo, RV10 – H.263, RV13 – H.263, RV20 – H.263+, RV30 – H.264 precursor, RV40 – H.264 precursor, and RVTR – H.263+ (RV20) video codecs. They can also work with lpcJ – RealAudio 1.0 (VSELP), 28_8 – RealAudio 2.0 (LD-CELP), dnet – AC3, sipr – Sipro, cook – Cook, atrc – ATRAC, ralf – RealAudio Lossless Format, raac – LC-AAC and racp – HE-AAC audio codecs.

Brief History

The RM file format was popular with modem-based connections, as it provided a higher compression that facilitated the streaming of video and audio files. However, the result was not a very good quality.

File Signature

ISO 88859-1:  .RMF

Hexadecimal: 2E 52 4D 46

Programs That Open RM Files


  • File Viewer Plus
  • RealNetworks RealPlayer Cloud
  • VideoLAN VLC media player
  • GRETECH GOM Player
  • Applian Replay Converter
  • Xilisoft Video Converter Ultimate
  • Online Media Technologies AVS Video Converter
  • Aiseesoft Video Converter Ultimate


  • RealNetworks RealPlayer Cloud
  • VideoLAN VLC media player
  • Aiseesoft Video Converter Ultimate
  • Eltima Elmedia Player


  • RealNetworks RealPlayer Cloud
  • VideoLAN VLC media player


  • RealNetworks RealPlayer Cloud
  • olimsoft OPlayer


  • RealNetworks RealPlayer Cloud

How to Recover Deleted RM Files

It is painful to lose some of our memories, work files, videos, etc. An unintended deletion is a common thing in our present digital lives.

Disk Drill is an app that helps in this type of situation. It is a data recovery program that is available for free!

Disk Drill
Data recovery for free
Your Companion for Deleted Files Recovery

The process to recover RM files is straightforward. Just follow these easy steps:

  1. Download Disk Drill from one of the links above.
  2. Install Disk Drill by clicking on the app’s icon. Then, follow the steps given to you. The program will do the hard work.
  3. Open Disk Drill. The app will detect all connected devices and list them. Disk Drill supports a wide variety of drives, such as internal and external hard drives, USB flash drives, memory cards, iPods, and many more. Select the drive that contains your lost files.
  4. Narrow the search by selecting the “rm” file format from the main menu.
  5. Start the scan. Disk Drill uses powerful algorithms to detect content still available on the drive. These algorithms are based on the principle that when we delete a file, we actually only remove a reference to it, but the content remains intact until overwritten by the operating system.
  6. You can pause or cancel the process. You can also save the session and continue later on, without any loss of the work already done.
  7. Once the scan is done, Disk Drill shows the results in the form of a list. You can narrow it by using filters according to date or size. Select the files you want and retrieve them to a folder of your choice.

Your RM recovery is done!

recover deleted rm

How to Use Image Files to Recover RM Files

Image files are a bit-by-bit copy of a digital drive. They are a very useful tool in RM file recovery, as you can work on them, keeping the original source unmodified.

Disk Drill is the perfect tool to use with image files, because it helps you to create the copy and then to search for deleted files using the image copy.

Image file usage is a standard practice in Digital Forensics. They are also useful for backup purposes. On the downside, they can contain unused space.

Arthur Cole

Arthur Cole is a freelance content creator. He also has a more than 10-year experience in program development for macOS, Windows, iOS, Android. Arthur Cole is a writer with deep expertise in programming, who can easily...

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Approved by
Brett Johnson

This article has been approved by Brett Johnson, Data Recovery Engineer at ACE Data Recovery. Brett has a Bachelor's Degree in Computer Systems and Network, 12 years of experience.