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Burned-in MP4

Burned-in MP4

An MP4 video file with subtitles permanently rendered into the pixel data, not as a separate caption track.

In depth

A burned-in MP4 has captions baked directly into the video frames during export. The captions are visible to every viewer on every platform regardless of caption support — there's no separate text track to lose. The trade-off: viewers can't toggle captions off, switch languages, or restyle. Burned-in MP4s are the standard delivery format for short-form social where captions don't survive cross-posting (TikTok, Reels, Shorts, X).

When to use it

Export a burned-in MP4 for short-form social, ad creative, and any deliverable where you don't trust the destination's caption rendering. Use a separate SRT for long-form YouTube and accessibility-critical contexts.

Frequently asked

How is a burned-in MP4 different from a regular MP4?+

Same container, same codec — only the pixel content differs. A burned-in MP4 has captions rendered into the frames; a regular MP4 has separate or no caption tracks.

Can a burned-in MP4 also have a soft caption track?+

Technically yes — you can mux a sidecar SRT track into the MP4 container alongside the burned-in captions. Most workflows ship one or the other, not both.

Related terms
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