Export ASS subtitles from video in one browser workflow

A transcript export is not an ASS delivery

Getting words and timestamps out of a video is only the first part of an ASS workflow. A client asking for ASS may expect positioning, outline, background, speaker treatment, karaoke, or local emphasis to remain editable. Converting a basic SRT at the last minute produces an ASS file extension, but not necessarily the reviewed render recipe.

The stronger workflow builds the subtitle state while the video is present. Timing, line breaks, safe-area placement, and contrast can be judged against the real frames before the file is handed off.

CutCaption connects video ingestion, caption editing, styling, libass preview, and ASS download inside one browser project.

Choose the starting track

There are two supported ways to begin:

• Generate captions from the video. The AI path creates editable cue timing and, when supported, word-level timing. Speaker detection can be requested on every plan.
• Attach an existing subtitle file. Manual import supports SRT and VTT when the transcript and cue timing already exist.

CutCaption does not currently import arbitrary ASS files for round-trip editing. It produces ASS from the caption state created or imported through these supported paths.

Prepare the ASS result

1. Correct the transcript against the source audio.
2. Adjust cue starts, ends, splits, and merges.
3. Correct individual word timing when the track includes it.
4. Set the global font, size, color, outline, shadow, background, margins, and position.
5. Add speaker treatments, local text overrides, per-cue positions, or effects where needed.
6. Review the saved state through JASSUB/libass over the actual video.
7. Download ASS on Creator or a higher plan.

This order prevents styling work from hiding transcript and timing problems. It also makes the final preview a direct check of the file model being delivered.

What to package with the file

ASS is separate from the video. The person opening it needs the matching media, and a playback or render environment that supports ASS/libass behavior. Custom fonts may also need to be supplied and installed in that environment.

Include:

• the approved .ass file;
• the matching video or an exact media filename reference;
• any licensed custom fonts the recipient is allowed to use;
• a note about the expected resolution or aspect ratio when placement is important.

If the recipient should not have to reproduce the environment, export a burned-in video instead. That fixes the approved subtitle pixels into the picture.

Check the handoff, not just the download

Open the ASS file with the target video in a compatible player such as one using libass. Check the first cue, the longest line, a local override, and a time-based effect. Confirm that the recipient’s font setup does not change wrapping.

For detailed styling boundaries, read the online ASS subtitle editor guide. For why the browser approval surface matters, see subtitle preview that matches export.