RealText to TTML Converter
FileFlip converts RealText to TTML 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 RealText file to TTML?#
- Drop your RealText 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 TTML 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 TTML file. Your browser writes it straight to your downloads folder, because there was never a server holding it.
Does converting RealText to TTML lose quality?#
No. Subtitle cues are text, and converting RealText to TTML rewrites the same timings and the same lines in the target's syntax. Anything TTML has no syntax for, such as positioning or styling, is dropped rather than degraded.
Is it safe to convert RealText files online?#
Yes, because nothing is uploaded. FileFlip converts RealText 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 RealText to TTML actually does to the file#
Converting RealText to TTML runs on FFmpeg, downloads 30.8 MB of WebAssembly the first time and nothing after that, rewrites the cues as text in the target's syntax, keeps cue durations.
| Engine | FFmpeg |
|---|---|
| Conversion path | One step: RealText → TTML |
| Downloaded to your browser | 30.8 MB, once, then cached by your browser |
| Quality | Text preserved, unsupported styling dropped |
| 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 |
|---|---|---|
| Cue durations | Kept | Carried through into the converted file. |
What is an RealText file?#
An RT file is a RealText caption script, a tagged markup text track that RealNetworks built for the RealPlayer streaming stack, using <br/> tags for line breaks and reference by a SMIL presentation to time captions against RealMedia audio or video.
Recognize RealText as a legacy RealPlayer caption file if it turns up alongside old RealMedia content; there's little reason to author new captions in it.
Convert RealText to SRT or VTT to caption the content on any current player, since RealText support has effectively disappeared outside archived RealPlayer installs.
What is a TTML file?#
A TTML file is an XML document that marks up timed text with a <body> of styled, positioned regions and a series of <p> elements carrying start and end times, built to move captions between broadcast and streaming systems without losing formatting.
Use TTML when delivering captions into a broadcast or streaming pipeline that expects it, such as Netflix's or the EBU's ingest specifications.
Convert TTML to SRT or VTT when the destination is a general video player rather than a broadcast or streaming delivery system, since those rarely parse TTML directly.
RealText to TTML questions people ask#
What is an RT (RealText) file?
An RT file is a RealText caption script, a tagged text format RealNetworks built to caption RealMedia audio and video played through RealPlayer. It's referenced by a SMIL presentation, which supplies the timing that syncs the captions to the media.
Can I still play RealText files today?
Rarely without the original RealPlayer software, since RealText was built for the RealMedia streaming stack and current browsers and video players don't support it natively. Converting the file to SRT or VTT is the practical way to use those captions with a modern player.
Is RealText the same thing as SMIL?
No. SMIL is the markup language that lays out and times a RealMedia presentation, and RealText is one of the pieces it can reference, a captions file the SMIL presentation calls in and synchronizes with the audio or video.
What is a TTML file used for?
A TTML file carries styled, timed captions through broadcast and streaming delivery pipelines, the way Netflix, the EBU and other distributors specify for ingesting subtitles. It's built for interchange between systems, not for opening directly in a typical media player.