2 Replies
Christy Tucker

There are a couple of sets of standards you can use. This DCMP standard says:

  • 32 characters per line
  • No more than 2 lines of text at a time

https://www.3playmedia.com/2015/11/06/dcmp-closed-captioning-standards/

The standard about having it on screen long enough to read I have seen interpreted as 1-6 seconds. That is, the caption should be on screen for at least 1 full second and no longer than 6 seconds (and either one of those extremes is probably less than ideal). You're mostly aiming for captions to be on screen for 2-5 seconds, breaking at natural pauses.

The BBC has a slightly different set of standards. I think either of these sets of standards are fine if you use them consistently. I find the DCMP standard to be a little easier to understand.

http://bbc.github.io/subtitle-guidelines/