Burn-in subtitles
Drop a video and a matching .srt file - captions will be rendered permanently into the picture.
Video
Subtitle file (.srt)
About this tool
Burn an SRT subtitle file permanently into a video. The subtitles become part of the picture and play on every device - important for social platforms (Instagram, TikTok, X) that strip soft subtitles, autoplay-muted feeds, and any player that doesn't honor a separate subtitle track.
Privvert renders the SRT timing and styling through FFmpeg's subtitles filter. The output is a normal MP4 you can upload anywhere. The whole process happens locally - your video and subtitles never go to a server.
Hard-coded subtitles are pixels - they cannot be turned off, restyled or translated by the viewer. That is the point: every social platform that autoplays muted (Instagram, TikTok, X, LinkedIn) silently strips soft subtitle tracks, and even YouTube users with captions disabled will see your burned-in text. If you publish anywhere captions matter, burning is the only guarantee.
Features
- Hard-coded subtitles via FFmpeg's subtitles filter
- Reads SRT (SubRip) files
- Uses the SRT's own styling and timing
- Output is H.264 MP4 for universal playback
- Reads MP4, MOV, MKV, WebM and most other source formats
- Browser-only - both files stay on your device
- Free and unlimited
How to use it
- Drop in your video and your .srt subtitle file.
- Click Burn.
- Wait while FFmpeg renders the subtitles into the video.
- Download the subtitled MP4.
Everything happens inside your browser using JavaScript and WebAssembly. Your files are never uploaded to a server, never stored, and never seen by us.
Frequently asked questions
Burning is permanent. For soft subtitles, mux the SRT into an MKV container with a subtitle track - that's a different workflow.
Most social feeds (Instagram, TikTok, X, LinkedIn) autoplay videos muted and strip soft subtitle tracks. Burned subtitles are the only way to guarantee viewers see the captions.
Style overrides go in the SRT itself or via an .ass subtitle file (advanced). For most users, the default look is clean white text with a black outline.
Use the Privvert audio/extract + an external transcription service (or a paid tool like Whisper) to generate one. SRT is plain text - you can also write one by hand for short clips.
SRT is plain text with timing only - no styling. ASS (Advanced SubStation Alpha) supports fonts, colors, positions, fades and karaoke effects. Burn an ASS file when you need designer captions; SRT is fine for plain readable text.
No - the runtime and audio track are untouched. Only the video pixels are re-encoded to draw the subtitle text into each frame for the duration the SRT specifies.