How do I add subtitles to a video automatically?

Choose a video, set the spoken language, and generate subtitles. Review each timed line beside the video, then download SRT or VTT or render captions into an MP4.

Can I add subtitles to an MP4 for free?

Yes. Zolkit accepts MP4 and other common browser-decodable video formats and does not charge per minute. Subtitle files and local captioned-video rendering are free.

What is the difference between downloading SRT and burning subtitles?

An SRT file is a separate, switchable subtitle track supported by many players and platforms. Burned subtitles are permanently drawn into the video picture and remain visible everywhere.

Is my video uploaded?

No. Zolkit extracts audio, runs Whisper, previews captions, and renders the final video on the device. The browser may download model and processing files, but the selected video is not sent to an API.

Can I edit automatic captions before exporting?

Yes. Every timed caption is editable, and selecting a line seeks the video to that point so wording and timing can be checked against the source.

Which subtitle format should I use?

Use SRT for broad compatibility with video platforms and editors. Use WebVTT for HTML5 video and web publishing, or burn subtitles when they must always appear in the picture.

Add Subtitles to Video with AI

Let AI generate multilingual captions, review every line, then download SRT, VTT, or a captioned MP4—all in your browser.

Drop a video here

or click to choose from your device

MP4, MOV, WebM, MKV or M4V

Choose how to use your subtitles

After AI generation and editing, download a subtitle file or create a video with captions permanently visible.

SRT: Widely compatible subtitles for video platforms and editors.
VTT: Web subtitles for HTML5 players, websites, and courses.
MP4: A shareable video with subtitles burned into the picture.

Automatically Add AI Subtitles to Video Online

Zolkit uses AI to extract speech and create timed captions beside an editable video timeline. The source video is not uploaded: AI transcription, preview, subtitle export, and MP4 rendering happen in the browser. Under the hood, a self-hosted Whisper model provides multilingual speech recognition.

AI multilingual captions

Use AI to create timed subtitles in multiple spoken languages, including Simplified and Traditional Chinese.

Video-synced review

Select a caption line to jump to its exact position in the video.

Editable subtitle timeline

Correct names, punctuation, and wording before exporting or rendering.

SRT and VTT downloads

Export standard subtitle files for YouTube, players, editors, and websites.

No video upload

Audio extraction and speech recognition take place on the device.

Captioned MP4 export

Burn captions into a shareable MP4 locally without a per-minute API fee.

How to Add Automatic Subtitles to a Video

1
Choose a video and select the spoken language or automatic detection.
2
Generate subtitles, play the video, and correct text in the synced timeline.
3
Download SRT or VTT, or burn the reviewed subtitles into an MP4.