Tools › Video
Burn subtitles into a video
Hardcode .srt or .vtt subtitles into an MP4 with your font, size, color, outline and background box. Arabic, Hebrew, Chinese, Japanese and Korean render correctly.
3 subtitles, until 0:06.0 · edit as text
How it works
- The subtitle file is parsed locally. SRT and WebVTT are supported, including styling tags, which are removed.
- A live preview shows every cue exactly where it will be burned in. Shift the timing if the subtitles run early or late.
- Each frame is decoded, the active lines are drawn on top, and the frame is encoded again with WebCodecs. Audio is kept.
Questions
Do right-to-left and CJK subtitles work?
Yes. Text is shaped by your browser, so Arabic joins correctly, Hebrew runs right to left, and Chinese or Japanese lines wrap between characters.
What about ASS or SSA files?
Not yet. Convert them to SRT first; most subtitle editors can.
Will the quality drop?
The video has to be re-encoded to draw on it. Nibbo uses a generous bitrate, so the difference is hard to see.
Which videos work?
MP4, MOV and M4V with codecs your browser can decode, which is H.264, HEVC on supporting devices, VP9 and AV1. WebM input isn’t supported yet.