Speed, over time
Core Web Vitals monitoring that shows real-user and lab numbers apart
Growth Radar monitors Core Web Vitals for every site: LCP, INP and CLS, with real-user field data from Chrome kept separate from lab test runs. You get a 30-day trend, the specific pages and files holding each score back, and a note when a number is missing instead of a made-up zero.
What it measures, and how
Field and lab numbers answer different questions, so they are labelled and never blended.
- Field data
- What real Chrome visitors experienced over the recent period, where the site has enough traffic for Google to report it.
- Lab runs
- A scripted mobile or desktop test, which works for any site and lets you see the effect of a change quickly.
- Thirty-day trend
- Every successful run in the last 30 days, so a regression shows up next to the day it started.
- The fixes
- The audit lists the speed problems it found on each page, with the steps to fix them.
Why INP is sometimes blank
Interaction to Next Paint only exists for real users, since a lab run has nobody tapping the page. When a site lacks the traffic for field data, Growth Radar shows the interactivity measure a lab run can give and tells you that INP itself is not available, rather than inventing one.
A speed fix is recorded when you ship it and read again after 28 days, so the trend line also says whether the work held.
What it can't see
- Small sites often have no field data at all, and the page says so.
- Lab scores vary between runs on the same page, so the trend matters more than any single number.
- Speed is one of many ranking signals. A good score does not by itself lift rankings.
- Pro is $49 a month for 5 sites and Agency is $199 a month for 50; every new account gets a 14-day free trial with no card.
Growth Radar or another tool
Suite tools include speed reports among many other features. Each claim below comes from the vendor's own page, linked. Checked October 28, 2026.
| Tool | Price | AI engines | Best for |
|---|---|---|---|
| Growth Radar | Free $0 (1 site); Pro $49 a month; Agency $199 a month; 14-day free trial, no card | Narrow: Perplexity, ChatGPT and Gemini, checked daily | Teams that ship SEO and GEO fixes as code on several sites and want each one graded win, loss or flat 28 days after it goes live |
| Semrush AI Visibility Toolkit | About $99 a month per domain; Enterprise AIO is quote-only | Not stated in the pages checked | Teams already on Semrush that want AI visibility next to their SEO data |
| Ahrefs Brand Radar | Index data from $199 a month, custom prompts from $50 a month, all AI models $699 a month, $0.02 per extra check | Google AI Overviews, AI Mode, ChatGPT, Perplexity, Gemini and Copilot | Teams that want market-wide share of voice from a pre-collected index of 514M+ prompts, with no prompt setup |
Sources: Semrush blog: AI visibility tools for agencies · Ahrefs Brand Radar
Common questions
What are the Core Web Vitals?
Three measures Google uses for page experience: Largest Contentful Paint for loading, Interaction to Next Paint for responsiveness and Cumulative Layout Shift for visual stability.
Why do field and lab numbers differ?
Field data comes from real visitors on varied phones and networks over weeks, while a lab run is one controlled test. Both are useful, and they are rarely identical.
How often are my Core Web Vitals checked?
Sites are re-read on a regular schedule, and the trend keeps every successful run from the last 30 days.
Is there a free Core Web Vitals check?
The free website audit reports phone speed for any domain with no signup.
Related
Try it on your own sites
Connect Search Console and the last 28 days import straight away. The trial needs no credit card.