Free SEO tool · Performance
Free Core Web Vitals Test: lab and real-user speed
Run Google PageSpeed Insights on one URL and read the results in plain language: a lab test of the page load, and — when Google has enough visits — what real Chrome users experienced over the last 28 days.
What does the free PageSpeed Checker analyze?
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1
Lab data
A Lighthouse test Google runs once, on a simulated device and network: performance score, LCP, TBT, CLS, FCP and Speed Index.
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Field data
Core Web Vitals from real Chrome users (CrUX), 75th percentile over 28 days — only when the page or site has enough traffic.
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Mobile and desktop
Each run tests one device type. Google mainly uses the mobile version of a page for indexing.
How to interpret your results
- ISSUE
- A clear fault that usually deserves a fix, e.g. a missing title or a non-200 status.
- WARNING
- May be a problem depending on the page, e.g. a missing description or canonical, or a long title.
- PASS
- Checked and looks fine.
- NOT CHECKED
- Not part of this check, or blocked by the site. The report says which — it is never counted as a fault.
PageSpeed Checker vs Website Audit vs SEO Monitor
PageSpeed Checker
One URL · free · no account
Lab and field performance results from Google PageSpeed Insights, explained in plain language.
You’re hereWebsite Audit
Many pages · free quick crawl
Crawls a limited set of pages and groups issues across your site, like duplicate titles and potential orphan pages.
Run a website audit →SEO Monitor
Connected data · account
Uses your Search Console and GA4 to track clicks, queries and changes over time.
Explore SEO Monitor →FAQ
Frequently asked questions
About the PageSpeed Checker.
01
What is the difference between lab and field data?
Lab data comes from one simulated test run — good for finding causes. Field data is what real Chrome users experienced over 28 days — it is what Google’s page experience signals use. They often disagree.
02
Why is there no field data?
Google only publishes real-user data for pages and sites with enough Chrome traffic. Smaller sites often have none; the lab test still works.
03
Why does the score change between runs?
Lab tests vary with network, server load and third-party scripts. Compare several runs, and trust field data for the long-term picture.
04
Is it free?
Yes. Results come from Google’s free PageSpeed Insights API, which has a daily quota. We cache each result for an hour and limit runs per visitor.
