Caption readability check
Subtitle Reading Speed Checker
Estimate how much reading each subtitle asks viewers to do during its screen time. Review characters per second and words per minute cue by cue, with a configurable CPS threshold.
Start with 3 free minutes
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Tool workspace
No account required · processed locally
17 CPS is a practical review starting point, not a universal rule.
Three steps
How this tool works
- 1
Add a valid SRT subtitle track.
- 2
Set the characters-per-second limit.
- 3
Review cues that need more time or shorter text.
Useful for
Common workflows
- Accessibility review
- Fast-paced Shorts captions
- Course and explainer subtitles
What it checks
Focused, transparent output
- Characters per second
- Words per minute
- Cue-level threshold flags
Questions
Frequently asked questions
What is CPS in subtitles?
Characters per second divides visible non-space characters by the cue duration.
What CPS limit should I use?
Standards vary by audience and platform. Start around 17 CPS, then account for language, age and content complexity.
Why can a short caption still be too fast?
A small amount of text can be difficult to read when the cue appears only briefly.