Subtitle speed checker

List cues that are too fast, too long, or overlapping.

What it does: Checks characters per second, line length, and line count against limits you set.

What it does not: Not a YouTube Shorts or TikTok certification. Limits are illustrative.

Limits: Paste SRT in this tab. Optional duration, gap, and WPM checks sit under Optional checks.

SRT

Max CPS Max characters Max lines

Shift ms

00:00:00,000

Local video

Safe-zone overlay reviewed 4 November 2026. Illustrative, not a platform spec. Ctrl+Enter exports.

The sample’s “Fast” cue is 20.0 characters per second. The first line is 81 characters.