Caption Cleanroom · local caption QA

Caption CPS checker

Characters per second (CPS) is a quick way to spot captions that may be dense for a viewer. Caption Cleanroom calculates it in your browser and compares each cue with the selected advisory release profile.

How to use it

1. Open the local SRT/VTT QA tool.
2. Choose General SRT/VTT, YouTube-basic SRT, or WebVTT-browser.
3. Review dense cues alongside timing, line-shape, duplicate, markup, and gap advisories.

CPS is a heuristic, not a readability, accessibility, or platform-certification decision. No caption text is uploaded, stored, tracked, or sent to an account.

Open the CPS checker → · SRT validator · VTT validator · SRT overlap checker