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TTML to SMI converter, without the upload.

Turn TTML subtitles into SMI. It is converted in your browser, so the file never leaves your device.

Drop TTML files here

or choose from your computer paste with Ctrl V

Ready · other file types work too0 bytes uploaded, ever

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How to convert TTML to SMI

  1. Add your TTML subtitles

    Drop TTML (DFXP) files onto the box above, or click it to choose them. ToAny reads the file's contents to detect the type, so a wrong extension does not matter.

  2. SMI is already chosen

    Press Convert. There is nothing else to set. The work happens in this tab.

  3. Download

    Save the SMI, or download everything as one ZIP if you converted several files.

Why ToAny

  • Private by construction

    The TTML to SMI converter is part of this page and runs inside your browser. Your subtitles are never sent to ToAny or to anyone else.

  • No upload, no queue

    Nothing has to travel to a server and back, so the conversion starts the moment you press Convert, even on a slow connection.

  • Free, without an account

    No sign-up, no email address and no watermark. Add several files and download them together as a ZIP.

TTML to SMI: what to expect

TTML is verbose XML that many consumer players cannot read. SMI can carry several languages in one file for the players that read it. TTML is at home in subtitles delivered to broadcasters and streaming services; SMI is the usual choice for subtitles for Korean-market players and multilingual files.

The text is read as UTF-8 or UTF-16, whichever the file is. An older file in another code page is read using the charset it declares, or as Windows-1252 if it declares none, so accented letters in an unlabelled legacy file can come out wrong. A file that is not text, such as the picture-based subtitles of a DVD, is refused instead of being converted to nonsense. Of the styling, only italic, bold, underline and the position on screen (top, middle or bottom, left, centre or right) travel between formats; fonts, colours, outlines and effects do not. Times in clock, offset, frame and tick form are all understood, and a region's position is kept as the cue's position. The file is written with one language class, and cues that overlap in time are shown together, as SAMI has a single timeline.

TTML vs SMI

TTML

TTML subtitles

TTML is the W3C's XML subtitle format. Streaming services and broadcasters deliver captions in TTML profiles such as IMSC. It can describe regions, styles and timing precisely, but it is verbose, and many consumer players do not read it. DFXP is an earlier profile of it.

Opens in Broadcast and streaming systems, Apple and Netflix workflows, and some video players

TTML converter
SMI

SAMI subtitles

SAMI is an HTML-like subtitle format from Microsoft, with each cue a SYNC tag holding the start time in milliseconds. It can hold several languages in one file, selected by style class. It is most common in South Korea.

Opens in Windows Media Player, KMPlayer, PotPlayer, VLC and Korean-market players

SMI converter
TTML compared with SMI
TTMLTTML subtitlesSMISAMI subtitles
Stands forTimed Text Markup LanguageSynchronized Accessible Media Interchange
TypeSubtitlesSubtitles
CompressionNone (XML text)None
Introduced2010, by the W3CThe late 1990s, by Microsoft
Opens inBroadcast and streaming systems, Apple and Netflix workflows, and some video playersWindows Media Player, KMPlayer, PotPlayer, VLC and Korean-market players
Best forSubtitles delivered to broadcasters and streaming servicesSubtitles for Korean-market players and multilingual files
File extension.ttml, .dfxp.smi, .sami

Questions

Are my subtitles uploaded anywhere?

No. The TTML to SMI conversion runs inside your browser, on your own phone or computer. The file is not sent to ToAny or to anyone else.

Is anything lost when converting TTML to SMI?

No further quality is lost: SMI stores the decoded audio exactly. The result is identical in content.

Can I convert several TTML files at once?

Yes. Add as many as you like, convert them together and download each result or all of them as one ZIP.

How do I convert TTML to SMI on Windows, Mac, iPhone or Android?

The steps are the same everywhere because ToAny runs in the web browser: open this page in a current version of Chrome, Edge, Safari or Firefox, add the TTML file, press Convert and save the SMI. There is nothing to install.

Is there a file size limit?

Yes, but a subtitle file is small. Files up to 50 MB are accepted, far more than any real subtitle file. Beyond that the limit is your device's memory, since nothing is uploaded; a computer copes with large files better than a phone.