A subtitle should stay on screen for a minimum of 1 second and a maximum of 7–8 seconds . Content & Formatting Best Practices Best Practices for Online Subtitling - EngageMedia
For adult programming, aim for 15–17 characters per second ; for children, aim for 12–15 CPS to ensure comfortable reading speeds. subtitle ccccc
Use a maximum of two lines of text at a time to prevent obscuring the visuals. A subtitle should stay on screen for a
Keep each line between 37–42 characters . aim for 15–17 characters per second
A good guide for effective subtitling (often referred to as "CCCCC" in academic or technical shorthand like "Clear, Concise, Consistent, Correct, and Complete") follows standard industry practices for readability and synchronization. Core Technical Standards