RM to NUT Converter
FileFlip converts RM to NUT entirely inside your browser, using FFmpeg compiled to WebAssembly. The file is never uploaded to a server: it is read off your disk, converted on your own machine, and saved back by the browser. That means no file-size limit, no queue and no account.
How do I convert an RM file to NUT?#
- Drop your RM file onto the converter at the top of this page, or click it to pick one from your computer. You can add as many as you like.
- Leave the target set to NUT and the conversion starts on its own. FileFlip downloads 30.8 MB of WebAssembly the first time and nothing after that, then runs FFmpeg on your own machine.
- Save the NUT file. Your browser writes it straight to your downloads folder, because there was never a server holding it.
Does converting RM to NUT lose quality?#
It depends on what is inside the file. RM is a container rather than a codec, so whether the NUT conversion copies the streams across untouched or re-encodes them is decided by the codecs that particular file happens to use.
Is it safe to convert RM files online?#
Yes, because nothing is uploaded. FileFlip converts RM files inside the browser tab you already have open, using WebAssembly builds of the same engines a desktop converter would install. Your file is read from your own disk into the page's memory, and no request carrying it is ever made.
You do not have to take that on trust. Open your browser's network panel, run a conversion, and you will see the engine come down and your file go nowhere. There is no upload, no server-side copy, no retention window, and no account tied to what you converted.
How FileFlip works lists every engine, its version and its download size, and shows how to check for yourself that nothing leaves your machine.
What RM to NUT actually does to the file#
Converting RM to NUT runs on FFmpeg, downloads 30.8 MB of WebAssembly the first time and nothing after that, re-encodes or copies through depending on the codecs in the file, and drops encoded streams.
| Engine | FFmpeg |
|---|---|
| Conversion path | One step: RM → NUT |
| Downloaded to your browser | 30.8 MB, once, then cached by your browser |
| Quality | Decided by the codecs inside the file |
| You get back | One file |
| Where it runs | In a background worker, so the page stays responsive |
What survives the conversion
| What is in the file | This conversion | Why |
|---|---|---|
| Encoded streams | Dropped | The target format has nowhere to put it. |
What is an RM file?#
An RM file is a RealMedia container from RealNetworks, holding RealVideo and RealAudio streams built for the dial-up era, when RealPlayer was how most people first watched video over the internet.
There is no current reason to create a new RM file; it only shows up now as something to get footage out of.
Convert RM to MP4 as soon as one turns up, since RealPlayer support keeps shrinking and most other software cannot open the format at all.
What is a NUT file?#
A NUT file is a general-purpose media container created inside the FFmpeg and MPlayer projects, built as a simple, open, patent-free alternative to AVI and similar formats, and able to wrap any codec those tools support.
NUT is worth using only inside an FFmpeg-based pipeline, such as a test harness or a tool chain that already standardises on it.
Convert NUT to MP4 or MKV for anything that needs to open outside FFmpeg or a player built on its libraries, since almost no other software recognises the container.
RM to NUT questions people ask#
What still opens an RM file?
VLC opens most RM files on Windows, macOS and Linux through its built-in libavformat decoder, which covers the common RealVideo codecs. RealPlayer itself still exists for Windows, Android and iOS, but RealNetworks stopped releasing it for macOS in 2018.
What should I convert an old RM file to?
MP4 with H.264 is the safe target for an old RM file, since it plays everywhere RealMedia no longer does, from phones to browsers to any current editing software.
Is RealMedia still used for anything?
No. RealMedia was the dominant streaming format before broadband made Flash and later HTML5 video practical, and it has had no meaningful new use since. An RM file today is almost always old footage someone is trying to recover, not something being created.
What opens a NUT file?
ffplay and mpv both open NUT files directly, since both are built on FFmpeg's own libavformat library, which is where the NUT container comes from. Outside that ecosystem, support is essentially nonexistent.