VIDEO SPEECH → TRANSLATED SUBTITLE FILE
Video subtitle translator.
Choose an MP4 video to start.
Experimental translation: the Spanish-to-English test misrecognized words. Review and correct every cue before using it.
Your video, audio and subtitle text stay in your browser. Only speech and translation model files download; no media bytes or speech text are uploaded.
Review the timed subtitles
Intervals without recognized words
What this page does
English speech is first transcribed locally, then translated into Spanish. Spanish speech is translated directly into English by a local multilingual speech model. One video creates one editable SRT or VTT subtitle file; it does not add a track to the video. To attach your finished file, use Add Subtitles to Video.
Tested limits
On this Windows test device, a 12-second, 181,452-byte English MP4 produced one editable Spanish cue in 37.5 seconds, including model loading; a 4.3-second, 41,665-byte Spanish MP4 produced one editable English cue in 25.8 seconds. Both downloaded subtitle files had a timestamped cue. These are observations for two short MP4 files, not a duration, size or speed guarantee. Audio capture plays the entire video locally at normal speed before recognition, so a long video takes at least its own runtime plus model processing. Other video formats and longer videos have not been verified on this page. Only English speech → Spanish subtitles and Spanish speech → English subtitles are offered.
The short Spanish test produced a cue that mixed English and untranslated Spanish words. This model cannot reliably deliver publication-ready subtitles: compare every line and timestamp with the source, then correct the editable text before downloading. It can also miss quiet speech, names, slang or technical terms. An inaudible video cannot produce subtitles.
Already have a subtitle file? Use SRT Translator or Translate VTT. Need English captions without translation? Use Auto Captions.
Translate a pasted timed transcript
If you have timestamped English text from a YouTube transcript, the YouTube subtitle translator makes editable Spanish SRT or VTT locally. It does not fetch a YouTube URL or scrape captions.