Documentation

Live data (RUM)

Measure real Core Web Vitals — snippet, metrics, sampling rate, weekly report and overview page.

What live data is

Live data measures the performance of your website with real visitors — directly in the browser, in real time. Instead of a lab scan with a simulated browser, it captures the actual Core Web Vitals of your users.

That adds an important perspective to scheduled scans: how do real visitors experience your site — on different devices, connections and locations?

Which metrics are measured

Metric What it measures Google recommendation
LCP (Largest Contentful Paint) Load time of the largest visible element max. 2,500 ms
CLS (Cumulative Layout Shift) Unexpected layout shifts max. 0.1
INP (Interaction to Next Paint) Response time to user input max. 200 ms
FCP (First Contentful Paint) Time until the first content is visible max. 1,800 ms
TTFB (Time to First Byte) Time until the server delivers the first byte max. 800 ms

LCP, CLS and INP are the three Core Web Vitals that Google uses to assess the user experience and that feed into search results.

How the integration works

You add a small JavaScript snippet to the <head> of your website:

<script src="https://turbometrics.io/tm.min.js" data-site-id="YOUR_SITE_KEY" async></script>

The script is around 5 KB (compressed), is loaded asynchronously and does not affect the performance of your page. It measures the web vitals of every page view and sends them to turbometrics in anonymised form.

You find the snippet code after creating a website under Live data > Embed code.

The p75 value: what it means

All metrics are evaluated as a p75 value (75th percentile). That means: 75% of your visitors had this value or a better one. The slowest 25% are filtered out so that individual outliers do not distort the overall picture.

Google uses the same approach for its Core Web Vitals assessment.

Data protection

  • IP addresses are anonymised immediately after the GeoIP lookup (last octet set to 0)
  • No cookies are set
  • No personal data is stored
  • The script contains no tracking and no fingerprinting

Sampling rate

Under Live data > [Website] > Sampling rate you control which share of page views is actually captured. Available options: 10%, 25%, 50%, 75% and 100% (default).

The decision is made per page_id — either all five metrics of a visit are stored or all of them are discarded. There are no partial measurements.

A lower sampling rate saves page view quota on heavily visited websites. The setting can be changed at any time without adjusting the embed code.

Weekly report

Once a week, turbometrics sends an email report with the following content:

  • score trends per domain — current value and change (± delta) versus the previous week
  • RUM data — LCP p75 with delta, page views, Core Web Vitals status
  • alert summary — alerts triggered and resolved in the last 7 days

The weekly report is enabled by default and can be configured under Profile > Notifications.

Overview page

The page at /rum shows all configured websites at a glance:

  • CWV status badges — passed / failed / not enough data
  • alert badges — number of active alerts per website
  • page views — values for the last 24 hours and for the current month
  • quota display — a bar with the current page view consumption

Two views are available: card view (default) and table view (switchable at the top right). The table view can be sorted by domain, LCP p75, page views and trend. The chosen view is stored in the browser and restored on the next visit.

Availability

Live data is available from the Starter plan onwards. The monthly page view limit depends on the plan:

Plan Page views / month
Free – (not available)
Starter 50,000
Pro 250,000
Agency 1,000,000

Further reading