Subtitle inspection
Basic SRT and WebVTT timestamps are parsed locally into milliseconds. The tool checks syntax, end-after-start validity, order, consecutive cue overlap, and flags short/long display windows and lines longer than 46 characters. Those reading thresholds are our heuristics, not formal platform standards. SRT output renumbers cues; styling/region features of rich WebVTT are not supported in conversions.
Shorts overlay preview
The adjustable warning bands are illustrative percentages of the preview frame. They are not measured from current official YouTube UI specs and can vary from real app overlays. Exported images are labeled as illustrations. Always verify your final placement in the mobile platform.
Upload-size estimate
The bitrate reference table is from YouTube's recommended upload encoding settings, checked October 2026 for standard dynamic range. Average video bitrate and audio bitrate are multiplied by video duration and divided by eight to estimate bytes. Decimal gigabytes and binary gibibytes are both displayed. The upload-time estimate applies a transparent 20% overhead assumption and is not an actual network measurement.
How we review claims
We prefer first-party provider documentation over unauthenticated content. All example costs, times and UI zones are clearly marked as estimates, examples or adjustable defaults. A technical pass from our tool must not be presented as proof of copyright permission, transcription accuracy or successful publication.
Questions or corrections: kimkidong1402@gmail.com.