Convert TTML
to ASS
Drop in a .ttml (Timed Text Markup Language) file, get a clean .ass (Advanced SubStation Alpha) back. Advanced SubStation Alpha is the heavily-styled subtitle format used by Aegisub and the fansub community. The conversion runs entirely in your browser — your captions never leave the page.
Frequently asked
Why convert TTML to ASS?+
Timed Text Markup Language is the W3C XML standard used by streaming platforms (Netflix, Disney+) and broadcast pipelines. Advanced SubStation Alpha is built for typography-rich subtitles, karaoke, kinetic typesetting. Converting lets you take a file produced for one workflow and use it in the other without re-typing or re-timing anything.
Is timing preserved exactly?+
Yes. The converter only re-encodes the file structure — start and end times round-trip to within one millisecond.
Does any styling survive the conversion?+
Both formats support styling, but the converter targets a clean output: tags and positioning are dropped, text and timing survive. Restyle in your editor of choice.
Does this run on a server?+
No. The conversion is pure JavaScript running in your browser — files never upload anywhere. Works offline once the page is loaded.