Free tool · ASSSMI

Convert ASS to SMI
for Windows Media and Korean broadcast

Convert an ASS (Advanced SubStation Alpha) file to SMI (SAMI — Synchronized Accessible Media Interchange) format. SMI is Microsoft's HTML-like caption format still required by some Korean and Japanese broadcast pipelines and legacy Windows Media workflows. Override codes and styling are stripped; timing and text are preserved.

Input · ASS
Output · SMI
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Frequently asked

What is SMI format?+

SMI (SAMI) is Microsoft's caption format from the Windows Media Player era. It uses HTML-like markup with <SYNC Start=milliseconds> tags. Still required by some Asian broadcast pipelines.

Why would I convert ASS to SMI?+

If a delivery spec requires SMI format — common in Korean broadcast and some legacy corporate video platforms that only accept SAMI files.

Are ASS styling and karaoke preserved?+

No. SMI has minimal styling support. Override codes, karaoke timing, and positioning are stripped. Only timing and plain text survive.

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