SUBTITLE QUALITY · MADE READABLE
WebVTT reading speed checker
Check WebVTT captions for reading speed and line length. Cue settings and formatting tags are handled in your browser.
01Your subtitles
No account required. No subtitle content is uploaded.
WebVTT is more than text
WebVTT can include cue identifiers, alignment settings, voice labels, and styling. CueCheck removes formatting from displayed text and skips NOTE, STYLE, and REGION blocks when calculating reading speed.
Use the visible duration
VTT timestamps may use minutes and seconds or include hours. Reading speed is based on the interval between each cue's start and end; it does not infer spoken-word timing from audio.
Review the warnings
Malformed blocks appear as warnings rather than silently disappearing. This is a readability review, not a complete WebVTT syntax validator. Check your video player's caption rendering too.
Questions editors ask
Which reading speed should I choose?
The reference English presets are based on Netflix's English (USA) guide: 20 CPS for adult programs and 17 for children's programs. Languages and clients use different limits. Set the thresholds required by your project.
Do spaces, tags, and line breaks count?
Spaces and punctuation inside a subtitle line count. Formatting tags are removed. Line-break separators are excluded. Counts use Unicode code points, rather than JavaScript string length; some emoji and combined letters use several code points.
Does CueCheck change my subtitles?
No. It reports potential readability and timing issues. Your original file stays unchanged. The downloadable CSV is a review checklist for your subtitle editor.
Can I check subtitles in another language?
Yes, Unicode text is supported. The provided thresholds are for English, so enter appropriate values for your target language and audience. This tool does not evaluate translation quality.
What information is collected?
Your subtitles and filenames stay local. Anonymous tool-page visits and control clicks help improve the site. You can disable that measurement on the privacy page.