Subtitle inspector
Check local SRT/VTT cues for overlaps, invalid timing and long lines. Shift time and download a clean file.
Open free tool →Built for creators who shipFinish the video.
Finish the video.
Catch the mistakes.
Then upload.
Practical, browser-only tools for subtitle timing, vertical-video overlays, and export size planning. Less guessing. Fewer avoidable re-uploads.
No account · No video uploads · No subscription
◉ LOCAL CREATOR QA BROWSER ONLY
BEFORE YOU PUBLISH
00:03Subtitle9:16Vertical1080pExport
Illustrative preview — calculations come from your inputs.
Real tools, not placeholders
Three checks before upload
Start with your biggest risk. Each tool works locally without uploading media to our server.
Shorts safe-zone preview
Try your own title over a 9:16 preview. Move adjustable risk overlays, then export a PNG.
Open free tool →Upload size & bitrate
Get official YouTube SDR bitrate references and estimate how large your file might become.
Open free tool →✓ Transparent assumptions✓ Local processing✓ Free exports✓ Official sources linked
Field guides
Useful answers, not filler
Short, practical guides with examples, edge cases, and source references.
SubtitlesWhy subtitle cues overlap — and how to fix themFix timing collisions without damaging the reading rhythm. →SubtitlesSRT vs WebVTT: choosing the right caption fileUnderstand timestamps, syntax, and converter pitfalls. →Vertical videoShorts safe areas: design for changing interfacesPlace titles and captions without guessing at fixed rules. →EncodingYouTube upload bitrate: 1080p, 1440p, and 4KUse official SDR reference values in practical exports. →EncodingEstimate video file size before renderingTranslate average bitrate, duration, and audio into disk space. →WorkflowThe small-creator video release checklistA repeatable last-mile review for every export. →
Have a subtitle file ready?
Drop it into the local checker. No upload or account required.