SRT Subtitle Checker: Line Length, CPS & Timing (embed)

Choose an SRT / VTT file or drop it here Read only in your browser or paste the subtitle text

Rules Preset

Max characters per line Max lines Target reading speed (CPS) Maximum (CPS) Min duration (s) Max duration (s) Min gap (frames) Frame rate (fps)

In the fixed SRT

Numbering, spaces, VTT → SRT, UTF-8 (always) Repair broken characters (e.g. “â€™” → ’, “Ã©” → é) Fix overlaps and gaps shorter than 2 frames Extend very short subtitles when there is room Close small gaps (under ½ second) to 2 frames Split lines that don't fit over two lines

Result

Show only subtitles with issues

Click a row to show it in the vertical preview below. CPS = characters per second (including spaces).

Burned-in subtitle preview (optional)

Burning captions into the video? Try the position and font size; you'll get a warning if the text ends up under the platform UI.

Format and UI

Vertical 9:16 Horizontal 16:9

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Font size (px) Vertical position (% from bottom)

Subtitle to preview Background frame (optional, a still from your video)