Captionly
on-device speech → captions
runs 100% in your browser

Caption style

Caption mode
Position
Distance from edge 6%
Font
Weight
Font size 28px
Text color
#FFFFFF
Active word color word-mode & karaoke
#FF7A50
Background color
#000000
Background opacity 65%
Padding 10px
Border radius 8px
Max width 80%
Text outline
Adds a soft dark stroke behind the text so captions stay readable over bright footage.
Style changes apply live to the preview and to your final download — no need to regenerate the transcript.

Preview

No video loaded yet

Drop a video, or click to upload
MP4 or WebM with an audio track works best. Everything happens locally — nothing is uploaded anywhere.
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Caption track 00:00 / 00:00
Generate captions to see the caption track here.

Speech recognition runs locally using a small Whisper model (via transformers.js). The first generation downloads the model once; your browser caches it for next time. Longer videos are processed in 5-minute segments for better performance.

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