Subtitle CPS / Reading-Speed Validator
A general subtitle QC pass — characters-per-second, line length, overlaps and durations — for when you just need clean, readable subtitles to no specific platform.
General readability — max 20 CPS, 42 chars/line, 2 lines, 0.7s min, 7s max
Not every job has a platform spec, but every subtitle file should be readable: ≤ 20 CPS, ≤ 42 characters per line, no overlaps, sensible durations. This is the sensible-default QC pass — run it on any SRT/VTT to catch the cues that flash too fast, run too long, or overlap their neighbours.
🔒 Subtitles are processed entirely in your browser — never uploaded.
A general subtitle QC pass — characters-per-second, line length, overlaps and durations — for when you just need clean, readable subtitles to no specific platform.
About Subtitle CPS / Reading-Speed Validator
A general subtitle QC pass — characters-per-second, line length, overlaps and durations — for when you just need clean, readable subtitles to no specific platform. Not every job has a platform spec, but every subtitle file should be readable: ≤ 20 CPS, ≤ 42 characters per line, no overlaps, sensible durations. This is the sensible-default QC pass — run it on any SRT/VTT to catch the cues that flash too fast, run too long, or overlap their neighbours.
How to use Subtitle CPS / Reading-Speed Validator
- 1Paste your subtitle file (SRT or WebVTT) into Subtitle CPS / Reading-Speed Validator, or open it from disk.
- 2The tool parses every cue and processes it in your browser.
- 3Review the result — flagged issues, converted output or statistics.
- 4Copy or download the corrected/converted file.
Why use Subtitle CPS / Reading-Speed Validator?
- ✓Runs entirely in your browser with instant, private results — no data leaves your device.
- ✓Built on a published reference: Subtitling readability conventions (CPS / CPL).
- ✓100% free with no sign-up, no watermark and no usage limits.
- ✓Works on any device — desktop, tablet or phone — and keeps working offline once loaded.
Frequently asked questions
What does Subtitle CPS / Reading-Speed Validator do?+
A general subtitle QC pass — characters-per-second, line length, overlaps and durations — for when you just need clean, readable subtitles to no specific platform. Not every job has a platform spec, but every subtitle file should be readable: ≤ 20 CPS, ≤ 42 characters per line, no overlaps, sensible durations.
Is my data private?+
Yes. Subtitle CPS / Reading-Speed Validator runs entirely in your browser — your inputs are never uploaded, stored or logged.
What standard or source is Subtitle CPS / Reading-Speed Validator based on?+
It follows Subtitling readability conventions (CPS / CPL). Always confirm against the current official document, as specifications and rates can change.
Is Subtitle CPS / Reading-Speed Validator free to use?+
Yes — it is completely free with no account, no sign-up and no usage limits. There is no watermark and no paywall.
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