📊 Free · no signup · no app install · read-only
What do your customers' phones actually experience?
These numbers are not a simulation. They come from the Chrome User Experience Report — the 28-day rolling field data Google publishes for origins with enough opted-in Chrome traffic, and the same dataset Search Console grades your site on. We read it for phones and for desktops and put the two side by side.
Based on publicly available data only. Informational, not legal advice.
What this checks
- Largest Contentful Paint at the 75th percentile, from real Chrome users on phones
- Interaction to Next Paint — how long the store takes to answer a tap
- Cumulative Layout Shift — how much the page moves around under the customer's thumb
- First Contentful Paint and field TTFB, both as measured on real visits
- Whether the origin passes Google's Core Web Vitals assessment (all three good at p75)
- How far behind phones are compared with desktops on the same store
- A single-shot look at how long the HTML document takes to arrive, and how heavy it is
FAQ
Where do these numbers come from?
From Google's public Chrome UX Report API. It is field data: an aggregate of what actually happened on real Chrome users' devices over the last 28 days, on real networks, on real phones. It is not a lab test and not a score we compute. That also means it lags — a fix you shipped yesterday will take weeks to move the 28-day average.
It says there is no data for my store. Does that mean my store is slow?
No — it means too few visitors. Google only publishes a CrUX record once an origin has enough opted-in Chrome traffic, so a young or low-traffic store simply is not in the dataset. We report that as “could not tell”, not as a failure. Note also that https://yourstore.com and https://www.yourstore.com are two different origins to CrUX; we follow your redirects and query the one your customers actually land on.
What can this tool not see?
Two real limits. First, CrUX data is per origin, not per page — we cannot tell you that your product template is the slow one, only that the store as a whole is. Second, we read your HTML exactly as the server sends it and never execute JavaScript, so we cannot tell you which element is your LCP element or which script caused a layout shift. Everything that needs a rendered page is marked “could not tell” rather than guessed at.
Want these watched every month, and the slow parts actually fixed?
We are a Shopify studio. The audit is free; the fix is yours to make — or ours to ship.
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