Check Chinese, Japanese and Korean subtitles against limits that fit the script, not English limits. The script is detected automatically, and you can override it.
Note: published guides disagree on exact limits, so these presets are editable. Change them to match the guide you follow.
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How to check CJK subtitles
Paste the subtitles and run the check. With auto-detect, the limits are set to the detected language's preset; change them if your guide uses different numbers, then check again.
Run the check, then reflow long lines. Reflow prefers punctuation and particles, and flags any line it had to split mid-string.
Common questions
Why not use English limits?One Chinese, Japanese or Korean character carries a whole word, so English limits of 42 characters per line do not fit. CJK guides use much lower limits.