Subtitle Readability Checker
Find captions that may be too fast, too dense or out of order before you publish a video.
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How to use Subtitle Readability Checker
- Paste SRT or VTT text, or open a UTF-8 file up to 2 MB and 10,000 cues.
- Adjust characters per second, line length and minimum duration to fit your audience and project.
- Review flagged cues, then export a CSV containing every cue and its checks.
When this helps
Catch a paragraph squeezed into one second, an overlong subtitle line or an accidental overlap. Use the report to guide editing and review, including translation workflows.
What to know before you start
The defaults are editable review thresholds, not a platform certification. The tool counts Unicode code points and strips markup for reading estimates. It does not judge translation accuracy, meaning or synchronization with speech. Some overlaps are intentional.
Frequently asked questions
Does a warning mean the subtitle is wrong?
No. It highlights a cue for review. Intentional overlaps, language and audience needs can change the right decision.
What does characters per second measure?
It divides visible text length, including spaces, by cue duration. It is a rough reading-density measure.
Will it rewrite the captions?
No. It produces a report so you can decide which changes are appropriate. Your source is unchanged.