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Web vitals

Speed you can see, next to the traffic it costs.

Flatlytics measures Core Web Vitals from the people actually using your site, and puts them on the same screen as the pages and sessions they affect. A slow page and what it costs you, together.

1.4sLCPgood90msINPgood0.04CLSgood

Real visitors, not a lab run.

Synthetic tests tell you how one machine loads your page once. Field data tells you how your actual audience experiences it, on their devices and their networks. Flatlytics collects the latter.

  • LCP, INP and CLS sampled from real sessions as they happen.
  • Broken down by page, so you fix the ones that matter first.
  • Next to the traffic each page carries, so effort follows impact.

The three metrics, and where the line is.

Each metric has a plain threshold for good and poor. We use Google's, and we show you which of your pages fall where.

LCP, Largest Contentful Paint

How soon the main content appears. Good ≤ 2.5s, poor > 4s.

INP, Interaction to Next Paint

How quickly the page responds when someone taps or clicks. Good ≤ 200ms, poor > 500ms.

CLS, Cumulative Layout Shift

How much the layout jumps around while loading. Good ≤ 0.1, poor > 0.25.

Straight about coverage

What field data can and can't tell you.

It's a sample, and we say so

Not every browser reports every metric, INP in particular comes from Chromium-based browsers, so vitals cover a sample of real sessions, not all of them. The product labels it as such.

Trends over single numbers

One session's LCP is noise. The distribution across many sessions is signal. Flatlytics leans on the trend, and shows you the spread, not just an average that hides the slow tail.

See your real-world speed.

Install one tag and watch Core Web Vitals arrive from your actual visitors, page by page.