Subtitle Generator Guide
Generate, edit, and export timed subtitles from audio or video locally.
Create editable subtitles from one audio or video file without uploading the media.
How to use
Supported input and limits
- Common WAV, MP3, M4A, AAC, OGG, Opus, FLAC, MP4, MOV, M4V, and WebM files.
- Up to 200 MB and 60 minutes per file.
- Processing is split into 10-minute windows and the result is limited to 10,000 cues.
The first run downloads the local FFmpeg, speech recognition, and voice-activity models. Keep the tab open. Later runs can reuse cached assets.
Privacy
Media, decoded audio, transcript text, timings, and exports remain on your device. Aiviko does not receive them.
Limits and troubleshooting
A supported extension does not guarantee codec compatibility. If decoding fails, try a WAV audio export or a shorter source. Recognition and voice-activity assets may be downloaded in addition to FFmpeg. Subtitle text and cue timings are drafts: review overlapping speech, silence, names and numbers before exporting. The tool exports subtitle files; it does not burn captions into a new video.
Related tools
Quick answer and specifications
The core workflow runs in this browser. Check the supported formats, published limits, and any on-demand model download before you start.
- Inputs
- WAV, MP3, M4A, AAC, OGG, Opus, FLAC, MP4, MOV, M4V, & WebM
- Outputs
- SRT, VTT, txt, & JSON
- Processing
- On this device, in the browser
- Model languages
- 100 languages — see the language selector
- Per-file limit
- 200 MB
- Files per run
- 1
- Media duration limit
- 60 min
- On-demand model download
- 99 MB
- Last verified
The interface language does not determine the model language. Recognition and pronunciation quality vary; check the result.