Find cues that flash by too fast, linger too long, overlap, or sit too close together. This tool checks each subtitle's duration and the gaps between cues against professional limits and flags the problems. It also reports reading speed. Runs entirely in your browser.
— or paste the subtitle text below —
A common standard (Netflix) is a minimum of 5/6 second (about 0.83s) and a maximum of 7 seconds per cue. Shorter than the minimum and it flashes by unread; longer than the maximum and viewers re-read it or think it is stuck. The defaults here follow those limits and are adjustable.
An overlap is when a cue starts before the previous one ends; a bad gap is when two cues are separated by less than a couple of frames, which reads as flicker. The tool flags both, plus reading speed, so you can catch timing problems before delivery.
A widely used standard is a minimum of about 0.83 seconds (5/6 second) and a maximum of 7 seconds per subtitle. Both are adjustable here.
When one cue starts before the previous cue has ended. Overlaps cause two subtitles to appear at once and should be fixed.
Yes. The same tool flags characters-per-second (CPS) reading speed alongside duration and overlaps.
No. Everything runs in your browser and the file never leaves your device.
These free tools handle files you already have. GeekLink extracts hardcoded subtitles via OCR, transcribes and translates with AI, and burns subtitles into video — batch-processing dozens of videos, all locally on your Mac or Windows PC.
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