Burn Subtitles into Course or Training Videos — No Upload
Some LMS players and embedded video systems ignore soft subtitle tracks. Burned-in captions make training content readable anywhere, especially for sound-off review.
Step-by-step
Prepare SRT, VTT, or ASS
Use SRT/VTT for simple captions. Use ASS if you need branded colors, outlines, or precise placement.
Burn subtitles locally
Drop in the video and subtitle file. Choose size and placement, then export an MP4 with captions drawn into the pixels.
Compress for LMS upload
If your LMS has a file-size cap, compress the captioned output after burning subtitles.
Recommended settings
| Subtitle inputs | SRT, VTT, ASS/SSA |
|---|---|
| Best output | MP4 H.264 + AAC |
| Typical caption size | 32-44 px for 1080p course videos |
Check before you publish
- Read a long line at the size you exported. 32-44 px for 1080p is the range where a caption is readable on a laptop and does not cover half the slide.
- Check captions against the slides, not just the audio. Text burned over a diagram is the most common complaint about course video.
- Confirm the timing at the end of a long lecture, where an SRT offset compounds and is most visible.
Tools you may also need
FAQ
Can students turn off burned captions?
No. That is the point: burned captions remain visible in any player and after download or re-upload.
Should I keep the subtitle file?
Yes. Keep the original SRT/VTT/ASS for edits and accessibility workflows even after exporting the hardsubbed video.
Does this run in my browser?
Yes — every step in this guide uses an in-browser FFmpeg WebAssembly tool. Your video never uploads to a server and never leaves your device.