SubtitleMedic

SubtitleMedic is a set of free online tools for repairing subtitle files. Shift subtitle timing or change the frame rate, sync one subtitle file against another, convert between SRT, VTT, ASS, SBV and SUB, export plain-text transcripts, fix broken encoding, merge two languages into one file, and clean out ad lines, SDH descriptions and formatting tags.

All processing happens in JavaScript inside the browser tab. Subtitle files are not sent to a server, and the tools keep working offline once the page has loaded. There is no sign-up, no upload limit and no queue. The site is available in English and Vietnamese and is supported by ads.