Track Core Web Vitals Over Time
RankNibbler tracks your site's Core Web Vitals continuously, so you see LCP, INP and CLS for both mobile and desktop, plotted over time and refreshed automatically. Every project gets Core Web Vitals from day one, using real-world data from your Chrome visitors where it's available and our own lab measurements otherwise.
Core Web Vitals that track over time, not a one-off score
Most Core Web Vitals tools give you a single reading the moment you press the button. RankNibbler tracks your site's Core Web Vitals continuously and plots them over time, so you can see exactly when a metric improved, when it regressed and whether a fix actually held. The trend chart covers LCP, INP and CLS, with Good and Poor threshold lines drawn in so a glance tells you where each metric sits.
Because the history keeps building, you get the picture point-in-time tools miss: how performance moves week to week, not just where it happens to be today.
Mobile and desktop, scored against the real thresholds
Core Web Vitals are tracked separately for mobile and desktop, because the two rarely behave the same. Switch between them with one tap and every metric, the trend chart and the overall status update for that form factor.
Each metric is graded against the standard Core Web Vitals bands: LCP is Good at 2.5 seconds or under and Poor above 4 seconds; INP is Good at 200ms or under and Poor above 500ms; CLS is Good at 0.1 or under and Poor above 0.25. An overall status sums it up as Passing, Needs improvement or Failing, so you know at a glance whether the page clears all three.
- LCP (loading) — Good ≤ 2.5s, Poor > 4s
- INP (responsiveness) — Good ≤ 200ms, Poor > 500ms
- CLS (visual stability) — Good ≤ 0.1, Poor > 0.25
- Overall — Passing only when all three are Good
Real-world data and lab measurements, clearly labelled
Where your site has enough Chrome traffic, RankNibbler shows real-world field data from your actual visitors, the same kind of experience data that reflects how people really load your pages. Where that real-user data isn't available, the page shows our own lab measurements instead, so every project has Core Web Vitals from day one.
The two are never blended into one line. Each reading carries a clear badge telling you whether you're looking at real-user data or a lab test, so you always know exactly what you're reading.
Auto-populated from day one, then refreshed for you
You don't set anything up. The moment you create a project, RankNibbler measures its Core Web Vitals in the background, pulling in roughly six months of weekly real-user history where it exists and capturing a fresh lab measurement, so the chart is already populated when you open the tab.
From then on, re-checks run automatically on a weekly cadence and quietly extend the history. When you want an immediate reading, the Refresh button starts a new measurement on demand and updates the page as soon as it's ready.
Built into your project alongside the rest of your SEO
Core Web Vitals sit inside the same project as your site audit, rankings and the rest of your SEO data, so page experience isn't a separate silo, it's part of the same view of your site's health. Because it's project-scoped, the metrics always track the site you're working on.
It's free with a RankNibbler account. There's no script to install, no tag to deploy and no separate monitoring subscription to manage.
How to track your Core Web Vitals over time
Three steps:
1. Create a project
Add your site as a project in RankNibbler. Core Web Vitals start populating automatically in the background straight away.
2. Open Core Web Vitals
Open the Core Web Vitals tab to see LCP, INP and CLS for mobile and desktop, each scored Good, Needs work or Poor with an overall status.
3. Watch the trend and refresh
Use the trend chart to follow each metric over time. Re-checks run weekly automatically, or press Refresh for an on-demand measurement.
Frequently asked questions
What are the three Core Web Vitals?
The three Core Web Vitals are Largest Contentful Paint (LCP), which measures loading; Interaction to Next Paint (INP), which measures responsiveness; and Cumulative Layout Shift (CLS), which measures visual stability. RankNibbler tracks all three for both mobile and desktop and scores each one Good, Needs work or Poor.
What are good Core Web Vitals scores?
A page is in the Good band when LCP is 2.5 seconds or under, INP is 200 milliseconds or under, and CLS is 0.1 or under. LCP is Poor above 4 seconds, INP is Poor above 500 milliseconds, and CLS is Poor above 0.25. RankNibbler grades every metric against these thresholds and shows an overall Passing status only when all three are Good.
Can I track Core Web Vitals over time?
Yes. RankNibbler keeps a running history of your Core Web Vitals and plots each metric on a trend chart with the Good and Poor thresholds marked, so you can see how LCP, INP and CLS move week to week rather than relying on a single one-off reading.
How often are Core Web Vitals updated?
RankNibbler re-checks your project's Core Web Vitals automatically on a weekly cadence, extending the history each time. You can also press Refresh at any point to start a fresh measurement on demand, which then updates the page once it lands.
Does it show real-user data or lab data?
Both, clearly labelled and never mixed. Where your site has enough Chrome traffic, RankNibbler shows real-world field data from your actual visitors; where that isn't available, it shows our own lab measurements, so every project has Core Web Vitals from the moment it's created. Each reading carries a badge telling you which one you're looking at.
Does it cover mobile and desktop separately?
Yes. Mobile and desktop are tracked and charted independently, because the same page often performs differently on each. You can switch between the two and every metric, the trend chart and the overall status update for that device.
Do I need to install anything to track Core Web Vitals?
No. There's nothing to install or configure. When you create a project, RankNibbler populates its Core Web Vitals automatically in the background, so the data is there from day one with no script, tag or extra setup.
Is Core Web Vitals tracking free?
Yes. Core Web Vitals tracking is free with a RankNibbler account. It comes with every project alongside your site audit and rankings, with no separate monitoring subscription required.
Track your Core Web Vitals
Create a project and your Core Web Vitals start tracking automatically — it's free.