PolyCaption

Add subtitles to your video

Upload a video and PolyCaption writes the subtitles for you. Fix any word, pick a style and export the video with captions burned in, or download an SRT file.

How it works

  1. Upload your video (MP4, MOV, WEBM).
  2. Check the automatic subtitles and edit any line.
  3. Pick a caption style and export the video or the SRT file.

Accurate, word-timed subtitles

Speech is transcribed with word-level timestamps, so each line appears exactly when it is spoken. Short-form styles split text into punchy two- or three-word captions for Reels, TikTok and Shorts.

Your video stays on your device

The video is processed in your browser. Only a small audio track is sent for transcription and it is deleted right after. Nothing is stored on our servers.

No watermark on the free plan

Free exports are clean. The free plan includes three videos a month of up to ten minutes each.

FAQ

Which video formats are supported?+

MP4, MOV, WEBM and most formats your browser can play. You can also upload audio files to get an SRT or a transcript.

Can I edit the subtitles?+

Yes. Every line can be edited, its end time adjusted or the line removed before you export.

How do I add the SRT file to YouTube?+

In YouTube Studio open the video, choose Subtitles, then Upload file and select the SRT you downloaded.