How to use it
- Drag in the caption file or paste the text.
- Choose a profile: TV and streaming for adults, children, or short vertical video. You can edit the limits.
- Review the table, where captions outside the profile are highlighted, and download the CSV report.
How it is calculated
Characters per second is the number of characters in the caption, without line breaks, divided by the time between its start and end. Markup such as <i> is not counted.
Standard versus suggestion
The TV and streaming profiles follow a major streaming service's public subtitle style guide: 42 characters per line, 2 lines, 17 characters per second for adult content and 13 for children. The short vertical video profile is only a suggestion, not an official standard, and you can adjust the numbers.
Frequently asked questions
What is a good subtitle reading speed?
The public reference for adults is up to 17 characters per second, and 13 for children's content.
Does the tool fix my captions?
No. It only lists captions that are too fast or too wide and lets you download a report. Editing the text is up to you.
Is the file uploaded?
No. Everything is calculated in your browser.
Read next
Like it? Generate the SRT straight from audio, with captions of at most 2 lines of 42 characters.
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