Subtitle CPS & Reading Speed Checker
Audit subtitle readability and Characters Per Second (CPS). Flags fast-reading lines (>20 CPS) to ensure accessibility for Netflix, BBC, and broadcast standards.
TL;DR: Subtitle CPS & Reading Speed Checker is a 100% free browser-based media utility. Audit subtitle characters per second (CPS) and flag lines exceeding broadcast reading speeds.
Select Subtitle File to Audit CPS Reading Speed
Flags lines exceeding 20 characters per second
Understanding Subtitle CPS & Reading Speed Checker
Audit subtitle readability and Characters Per Second (CPS). Flags fast-reading lines (>20 CPS) to ensure accessibility for Netflix, BBC, and broadcast standards. Designed for creators, video editors, audio engineers, web designers, and developers who need instant, high-precision processing without software installation, watermarks, or file uploads.
Mathematical Formula & Technical Methodology
Formula Variables Explained:
Calculates character presentation rate against Netflix/BBC maximum limits (17–20 CPS).
Step-by-Step Worked Example
A 40-character line shown for 1.2s has a CPS of 33.3 and is flagged as 'Too Fast to Read'.
100% Client-Side Privacy Guarantee
All media decoding, manipulation, calculations, and encoding execute locally inside your web browser using HTML5 Canvas, Web Audio API, WebCodecs, Web Crypto, and modern JavaScript engines. Zero server uploads, zero telemetry, and no registration required.
Frequently Asked Questions
- CPS measures reading speed. Standard broadcast limits are 15 to 20 CPS (Netflix/BBC). The checker highlights cues that are too fast for viewers to read comfortably.
Embed This Tool
Add the live Subtitle CPS & Reading Speed Checker to your own website with this embed code:
<iframe src="https://nexlove.org/embed/subtitle-cps-checker.html" width="100%" height="650" style="border:1px solid #e2e8f0;border-radius:12px" title="Subtitle CPS & Reading Speed Checker — NexLove" loading="lazy"></iframe>