Metadata · subtitles · captions
Subtitle QA.
Paste your book metadata and SRT/VTT cues. Get the hard errors and a quick readability pass without sending the transcript anywhere.
Paste to check
QA summary
Paste a title, subtitle, or timed text to see checks.
What the flags mean
The KDP metadata check treats title plus subtitle as a single string and passes only when it is fewer than 200 characters. Caption warnings use practical heuristics: 42 characters per line, 17 characters per second, and a 1–7 second cue window. They are editing signals, not a platform acceptance guarantee.
WebVTT timestamps must start at or after the previous cue’s start, and each cue’s end must be later than its start. Overlaps are reported because they are often accidental in subtitles.
Open the W3C WebVTT specification Open KDP metadata guidance