softsubs

Softsubs, or soft subtitles, are subtitle data that exist as separate text streams associated with a video file or stream rather than being burned into the image. They can be stored inside the container as a subtitle track, such as in Matroska (.mkv) or MP4, or provided as external subtitle files like SubRip (.srt), WebVTT (.vtt), or SubStation Alpha (.ass/.ssa). Because they are separate from the video, they can be enabled or disabled by the viewer and can be translated, edited, and synced without altering the video itself.

Compared with hard subtitles (burned-in subtitles), softsubs offer language choice and accessibility options but require a compatible video player and font rendering to display. They may be loaded as multiple tracks to present several languages; otherwise users may supply external subtitle files. Some platforms support automatic font sizing, color, and positioning, while others may render with limited styling.

Common subtitle formats include SRT, VTT, and SSA/ASS; many video containers support multiple subtitle tracks. Advantages include flexibility, localization, and accessibility; limitations include reliance on player support, potential font rendering inconsistencies, and the need to manage separate files or streams. In digital distribution, soft subs facilitate localization and accessibility without modifying the video content.