2 seconds on your MacBook. 8 seconds on your customer’s phone.

Tracks how fast your store loads every day, so you know the moment something slows it down.

What it checks

Daily performance scores — Performance, Accessibility, Best Practices, SEO
Core Web Vitals — LCP, CLS, INP per page
Mobile and desktop scores separately
Real-user field data from Google when available
30-day trend tracking with daily data points
PSI-standard colour thresholds (90/50)

What you don't know

A new app slowed your homepage by 3 seconds. You installed it last Tuesday.

Theme updates, new apps, unoptimised images — each one adds a few hundred milliseconds. Individually, nothing. Cumulatively, your mobile customers are waiting 8 seconds for your homepage to load.

Cassian™ runs daily performance audits via Google PageSpeed Insights and tracks your Core Web Vitals over time. When performance drops, you know exactly when it started — and what changed.

How Cassian™ detects this

Cassian runs Google’s PageSpeed Insights API against your pages daily — the same performance lab test Google uses for ranking signals. You get Performance, Accessibility, Best Practices, and SEO scores for both mobile and desktop, plus Core Web Vitals (LCP, CLS, INP). Real-user field data from Google is shown when available for your domain. 30-day trend charts track whether you’re improving or quietly degrading.

With Cassian™

  • Daily performance scores for mobile and desktop
  • Core Web Vitals: LCP, CLS, INP tracked over time
  • 30-day trends show exactly when performance changed
  • Real-user field data when available from Google

Without monitoring

  • Performance degrades invisibly over weeks
  • No baseline to compare against
  • Mobile performance ignored until complaints
  • No correlation between changes and speed impact

Plan access

All tiers. Free API — no additional cost on any plan.

Compare all plans →

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See it for yourself.

Enter your store URL and get your first scan in minutes. Free, no credit card, no commitment.

No credit card · Results in minutes · Free forever plan