Subtitle Overlap Checker
Find subtitle cues whose start time occurs before the previous cue has ended.
How to use the Subtitle Overlap Checker
What does the Subtitle Overlap Checker do?
Find subtitle cues whose start time occurs before the previous cue has ended; It applies this page-specific rule: a cue overlaps the next cue when its end time is later than the next start time.
Which inputs does this tool use?
To find subtitle cues whose start time occurs before the previous cue has ended, enter Subtitle content, Input format, Allowed overlap tolerance in seconds, Timing findings; keep every value in the same example; where available, choose between Detect SRT or WebVTT, SRT, WebVTT to match the required format; select Check subtitle timing when the values are ready; Start with a familiar case covered by this rule - Tolerance lets a known small overlap pass - so the expected result can confirm the settings.
How should the tool result be read?
For a result intended to find subtitle cues whose start time occurs before the previous cue has ended, tolerance lets a known small overlap pass; read timing findings together with the original subtitle content rather than as an isolated answer, and confirm that its units or structure match the intended use.
Is every overlap an error?
When the goal is to find subtitle cues whose start time occurs before the previous cue has ended, not necessarily.
What does tolerance mean?
When using the page to find subtitle cues whose start time occurs before the previous cue has ended, an overlap must exceed the entered number of seconds to be reported.
Limits and accuracy
When using this tool to find subtitle cues whose start time occurs before the previous cue has ended, cues are checked in file order; check the result in its intended destination before relying on it for important work; keep subtitle content until the output has been checked in its intended destination.
How subtitle overlaps are checked
A cue overlaps the next cue when its end time is later than the next start time. The report gives the overlap duration to three decimal places.
Tolerance lets a known small overlap pass. For example, a tolerance of 0.050 ignores overlaps of 50 milliseconds or less.
Cues are checked in file order. The page also reports when a later cue starts before the preceding cue, because sorting errors can make pairwise overlap reports misleading.
Frequently asked questions
Is every overlap an error?
Not necessarily. Some subtitle formats and production workflows intentionally overlap cues.
What does tolerance mean?
An overlap must exceed the entered number of seconds to be reported.
Does the tool reorder cues?
No. It reports file-order problems without changing the source.