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Are your Core Web Vitals passing?

Paste a URL and get your Google PageSpeed performance score plus the three Core Web Vitals — LCP, CLS and INP — with pass-fail coloring. Slow loads, jumpy layouts and laggy taps quietly cost you rankings and visitors; this shows you exactly where you stand on mobile.

Is your website fast enough on phones?

If you have ever wondered "is my website fast enough on phones?" you are asking the right question — most people only ever see their own site on a fast laptop with fast internet, so they never feel what a customer on a phone actually feels. This free Core Web Vitals checker (Core Web Vitals are how fast and how steady your page feels to real visitors) runs a mobile speed test and shows your Google PageSpeed score alongside the three numbers that matter — LCP, CLS and INP — in plain pass-fail colors. No signup, no jargon: just paste a page and see where you stand.

What this tool checks

Paste any page and it measures, on a simulated phone:

• Your overall PageSpeed score (0–100) — Google's single grade for how well the page is built for speed.
• LCP — Largest Contentful Paint: how many seconds until the biggest thing on screen (usually your main image or headline) actually shows up.
• CLS — Cumulative Layout Shift: how much the page jumps around while loading, the thing that makes you tap the wrong button.
• INP — Interaction to Next Paint: how quickly the page reacts the moment someone taps or clicks.
• Real-user field data when Google has it — measurements from people who actually visited your page over the last 28 days, not just a one-off test.

Why it matters

A slow, jumpy page quietly costs you on three fronts at once:

• Human visitors leave. People decide in a second or two whether a site feels trustworthy, and a page that stalls or jumps loses the sale before you ever get a chance to make it.
• Google uses Core Web Vitals as part of how it ranks pages. When two pages are otherwise equal, the faster, steadier one tends to win — and a painfully slow page can be held back.
• AI assistants (the chat tools more and more people now ask before they ever open Google) reach your site over the same connections people do. A page that loads cleanly and reliably is simply easier for any machine to read, quote and recommend.

How to read your results

Green is good, amber needs work, red is failing — that is the whole color code. For the score, 90+ is green, 50–89 is amber, and below 50 is red. For the three vitals, a good result is roughly LCP ≤ 2.5s, CLS ≤ 0.1, and INP ≤ 200ms, measured across the slowest quarter of your real visitors. If you see field data, trust it first — that is real people on real phones. If you only see lab data, it just means Google does not yet have enough traffic to your URL; the simulated mobile run is still a fair estimate. Re-run the check after you make changes — it reads the live page, so improvements show up once they are deployed.

What to fix first

If your score came back amber or red, start with the changes that move the needle most for the least effort:

1. Shrink your biggest images. Oversized photos are the number-one cause of slow LCP. Compress them and serve modern formats — this alone often turns red into green.
2. Reserve space for images, ads and banners. Giving every element a fixed size stops the page from jumping as it loads, which fixes most CLS problems.
3. Cut the heavy extras. Chat widgets, trackers and pop-up scripts are the usual reason taps feel laggy (poor INP). Remove what you do not truly need.
4. Then check the whole site, not just one page. A single fast page is a start, but your visitors and Google judge every page. The full free AUDXY website audit scores your whole site and tells you what to fix in order.

Related free tools

This checker tests speed on one page. To see the bigger picture, pair it with these free tools: the website checkup tool for a quick all-round health read, the heading structure checker to make sure Google and AI can follow your page's outline, and the social preview checker to see how your link looks when it is shared. Browse them all in the free tools hub.

Frequently asked questions

What are Core Web Vitals and why do they matter?

LCP (Largest Contentful Paint) measures how fast the main content appears. CLS (Cumulative Layout Shift) measures how much the layout jumps around as it loads. INP (Interaction to Next Paint) measures how quickly the page responds when someone taps or clicks. Together they grade how a page feels to a real visitor — and they feed into Google's ranking signals, so passing all three on a phone is a baseline for both search visibility and sales.

What is a passing Core Web Vitals score?

You generally want LCP ≤ 2.5s, CLS ≤ 0.1, and INP ≤ 200ms, measured across the slowest quarter of real visitors. A PageSpeed performance score of 90+ is green (well-optimized), 50–89 amber (needs work), and below 50 red (failing).

How do I check if my website is fast enough on phones?

Paste your page URL above and the tool runs a mobile PageSpeed test, then shows your score and your LCP, CLS and INP with pass-fail coloring. It checks the phone experience for you in about twenty seconds — the experience most owners never actually see, because they only ever browse their own site on a fast computer.

Why does my phone speed score differ from my desktop score?

Phones have slower processors and shakier connections than laptops, so the same page almost always scores lower on mobile. Since most visitors now arrive on a phone — and Google ranks using the mobile version of your site — the mobile score is the one that counts. This checker tests mobile by default.

What is the difference between lab data and field data?

Field data is real measurements from real Chrome users who visited your page over the last 28 days; it only appears once Google has enough traffic to your URL. Lab data is a single simulated mobile run that works on any page, even a brand-new one. Use field data as the truth about your visitors, and lab data as a fast, repeatable way to test your fixes.

Do Core Web Vitals actually affect my Google ranking?

Yes — they are part of Google's page experience signals. They rarely outweigh genuinely relevant content, but between two similar pages the faster, steadier one tends to win, and a very slow page can be held back. Just as importantly, speed keeps visitors from leaving before they read or buy, so a fix helps rankings and conversions at once.

Will fixing my Core Web Vitals help AI assistants find my site?

Indirectly, yes. AI assistants reach your pages over the same connections people do, and a page that loads cleanly is easier for any machine to read and quote. Speed alone will not get you cited, but a fast, stable, well-structured page removes a common reason you get skipped.