FIND THE CUES THAT NEED ATTENTION

Subtitle Overlap & Reading Audit

Inspect SRT and plain WebVTT subtitles for nested overlaps, fast reading, short gaps, brief or long cues and crowded lines. Change thresholds to suit your project; export a report without rewriting the source.

1. Subtitles & thresholds

SRT or plain WebVTTOpen UTF-8 subtitle file

Minimum duration (seconds)Maximum duration (seconds)Maximum code points per secondMaximum code points per lineMinimum gap (milliseconds)

2,000 cues · 300,000 text characters · 10,000 overlap pairs · 15-second worker limit. Uses the existing subtitle parser; unsupported VTT metadata, styles, regions and word timestamps are rejected.

2. Findings & cue details

Try the example or open your subtitles.

Show cues

Cue	Timing	Duration	CPS	Findings	Detail

Selected cue

Thresholds are adjustable starting values, not a broadcaster or accessibility certification. Intentional simultaneous dialogue can overlap. Review findings against the actual video.

How to review subtitle quality

Open an SRT or supported plain VTT file and set thresholds for your intended audience.
Run the audit and filter findings. View a cue to see its complete text, overlaps and preceding gap.
Download the full report; the preview displays at most 200 matching cues.
Make reviewed timing corrections in the Subtitle Timing Editor, then audit again.

How measurements work

All still-active cues are checked, so a long cue overlapping several later cues is detected even when those later cues do not overlap each other. Touching endpoints are not overlaps. Short-gap checks use the preceding occupied interval, not simply the preceding row.

Reading speed counts Unicode code points excluding line breaks after stripping tags and decoding a small set of HTML entities. It is an estimate, not a rendered-text or language-specific reading assessment. More than two lines is flagged separately. Invalid end-before-start cues are rejected by the shared parser rather than included in this report.

No automatic fixes, video rendering or transcript upload is performed. Reports contain cue text; handle them as carefully as the original.

Using Subtitle Overlap & Reading Audit

Find subtitle cues that need manual review without changing their source timing.

Open supported subtitle text and adjust project thresholds.
Audit, filter findings and view complete cue details.
Export a full report, fix reviewed issues in your editor and audit again.

Example

The sample includes a long cue spanning two later cues, fast text and a 20 ms gap.

Questions & answers

Does it detect nested overlaps?

Yes. Every still-active cue is checked against the current cue. Touching endpoints are not overlapping. Audits stop above 10,000 overlap pairs.

Are all flagged cues wrong?

No. Simultaneous dialogue and artistic timing can be intentional. Thresholds are configurable starting values, not a platform compliance guarantee. Review against the video.

What does reading speed count?

Unicode code points excluding line breaks after simple tag removal and limited entity decoding. It is not grapheme-based or a complete rendering of subtitle markup.

Which files are supported?

SRT and plain WebVTT through the existing subtitle parser, up to 2,000 cues and 300,000 characters. Unsupported VTT metadata, styles, regions and word timestamps are rejected.

Does it rewrite subtitles?

No. It produces audit reports only. Use a subtitle editor for reviewed fixes; exported reports contain cue text and should be treated as sensitive as the source.