FREE · SINGLE-FILE · NO UPLOAD

Catch subtitle problems
before you publish.

Open an SRT or VTT file to see overlapping timecodes, fast captions and problematic display durations. Review the actual findings in seconds, right inside your browser.

CHECK MY SUBTITLES ↗ SEE A REAL BEFORE/AFTER DEMO →

01 / SEE YOUR SUBTITLE QUALITY

Check a real file — or try the sample.

Your subtitle text is never sent to CueShift servers. This preview is informational, not a formal accessibility or broadcast certification.

No file checked yet. Select a file or load the example to see real findings.

02 / UNDERSTAND THE LIMITS

What we check — and what we don't.

Overlapping cues

Two consecutive timed captions overlap. This can cause unexpected stacking or subtitle flicker in different players.

Characters per second (CPS)

Text length divided by time on screen. Our adjustable default of 20 CPS is a pragmatic review threshold, not a guarantee of compliance.

Too short or too long

Cues displayed for less than 0.7 seconds or longer than 9 seconds are flagged for human review.

Source accuracy

Timing data cannot tell whether a speaker's words are correct, whether the captions sync with the video, or whether every subtitle style survives conversion.

Technical note: parsed cues are sorted by start time; this single-file preview does not detect original file order errors. It handles basic SRT/WebVTT text, not every advanced WebVTT styling directive. Subtitle quality always requires reviewing the final video.

03 / PAID WORKFLOW WHEN YOU NEED SCALE

QA one file free. Export a whole project with Pro.

Batch Studio Pro brings per-file caption QA reports, batch-wide CSV summary and multiple format conversions into one portable ZIP. Work offline with up to 200 files per run, so you can spot problem episodes before delivery.

SEE BATCH STUDIO PRO · $12 PLANNED →

Actual offline product is built. Checkout is not active until Creem approves our merchant account; no money is collected today.

PRO DELIVERY PREVIEWQA-REPORTS/001-episode-a-caption-qa.csv002-episode-b-caption-qa.csvBATCH-SUMMARY.csvReal files included in the offline Pro ZIP

04 / COMMON QUESTIONS

What should I know?

Does CueShift upload my captions to a server?

No. This page reads subtitle text inside your own browser tab. Cloudflare Web Analytics measures page visits and performance; it does not receive the content you paste or select.

Can I use the free checker before buying Pro?

Yes. You can check one file and export its results without registering or paying. The paid product focuses on working with hundreds of files and collecting reports in one local archive.

Does a clean report mean my subtitles are correct?

No. This tool checks only selected timing and readability heuristics. It cannot judge speech accuracy, localization, video synchronization, accessibility compliance or all styling details.

Can this page transcribe video or audio?

No. You must supply subtitle text from an existing SRT or VTT file. The separate Creator AI workflow works with transcripts; it is not included in the offline Pro download.