How to use it
- Choose the video.
- Load the .srt or .vtt file, or paste the subtitles into the box.
- Pick the text height, box or outline, top or bottom, and white or yellow. The preview shows the first subtitle on a frame.
- Shift the timing if needed, press Burn subtitles, then download.
How it works
The subtitle text is parsed into cues with a start and end time. While the video plays into a canvas, the cue whose time range contains the current moment (plus the shift) is drawn on each frame: centred, wrapped to 90% of the width, in a dark box or with a black outline. The canvas and the sound are recorded with MediaRecorder.
Worked example
The cue 00:00:04,000 --> 00:00:06,500 shows from 4.0 s to 6.5 s. With a shift of 1.5 it shows from 5.5 s to 8.0 s instead. On a 1080-pixel-high video at a text height of 5%, each line is 54 px tall.
Tips
- Yellow with an outline is easy to read over bright scenes; the dark box works on anything.
- Keep two lines per subtitle at most; the subtitle reading speed checker helps with timing.
- The file stays a normal video, so it can be shared to places that do not accept subtitle files.