SAMI Converter
FileFlip converts SAMI files into 6 other formats entirely inside your browser, using FFmpeg compiled to WebAssembly. The SAMI file is never uploaded to a server: it is read off your disk, converted on your own machine, and saved back by the browser. There is no file-size limit and no account to create.
How do I convert a SAMI file?#
- Drop your SAMI file onto the converter at the top of this page, or click it to pick one from your computer.
- Choose the format you want out of it. FileFlip downloads the engine that conversion needs, once, and your browser caches it.
- Conversion starts the moment you pick the format, and the result is yours to download. The work happens in this tab, so nothing is uploaded and nothing is queued.
Is it safe to convert SAMI files online?#
Yes, because nothing is uploaded. FileFlip converts SAMI 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 happens to a SAMI file#
FileFlip converts SAMI into 6 formats with FFmpeg, all of it inside the browser tab. Each conversion below names the engine it uses, what it downloads, and exactly what that conversion keeps or drops.
| Category | Subtitles |
|---|---|
| File extension | .smi |
| FileFlip support | Read only, so it is a source rather than a target |
| Conversions available | 6 |
| Engines | FFmpeg |
| Downloaded to your browser | 30.8 MB on the first conversion, then cached |
What is a SAMI file?#
A SAMI file is an HTML-flavored caption script built from <SYNC Start=milliseconds> blocks, each holding the caption text for one moment in the media, with CSS-style classes used to hold more than one language's captions in the same file.
Recognize SAMI as a legacy Windows Media caption file if it turns up alongside older video content; there's little reason to author new captions in it today.
Convert SAMI to SRT or VTT to caption video outside the Windows Media Player ecosystem, where SAMI support is inconsistent.
The SAMI file format reference covers the specification, the programs that open one, and what each conversion keeps or drops.
SAMI questions people ask#
What is a SAMI (.smi) file?
A SAMI file is Microsoft's caption format from the Windows Media era, marking up timed captions with HTML-like <SYNC> tags in a file that Windows Media Player loads automatically when it shares a video's filename. The name stands for Synchronized Accessible Media Interchange.
Why does my SAMI file show captions in the wrong language?
A SAMI file can hold more than one language's captions in the same file, each under its own CSS-style class, and the player decides which class to display. If the wrong language shows, the player is choosing a different class than the one intended, not that the file is broken.
Does Windows Media Player play SMI files automatically?
Yes. Windows Media Player looks for a .smi file with the same name as the video file in the same folder and loads its captions automatically, without the file needing to be selected manually.