Google PageSpeed Insights
Google PageSpeed Insights (PSI) is a free tool at pagespeed.web.dev that analyzes a URL and reports lab performance data (Lighthouse) and real-user data (Chrome User Experience Report). It provides scores from 0–100 for Performance, Accessibility, Best Practices, and SEO.
Why It Matters for Shopify Stores
PageSpeed Insights is the authoritative tool for measuring Core Web Vitals because it uses both lab data (controlled Lighthouse measurement) and real-user CrUX data. For Shopify merchants, the Performance score is most relevant — below 50 is poor, 50–89 needs improvement, 90+ is good. However, the Lighthouse score and the real-user CrUX score often differ significantly for Shopify stores with heavy JavaScript apps.
How to Check Your Store
Visit pagespeed.web.dev. Enter your store URL and separately test your most important product page URL. Run both mobile and desktop tests — mobile scores matter more for Shopify stores.
Use the free shopify speed test toolHow to Fix It
Follow the 'Opportunities' and 'Diagnostics' sections. Each opportunity includes estimated impact. Start with the highest-impact items: render-blocking resources, image optimization, unused JavaScript.
Related Terms
LCP (Largest Contentful Paint)
Core Web VitalsLargest Contentful Paint measures how long it takes for the largest visible content element on a page — usually a hero image or headline — to finish loading.
CLS (Cumulative Layout Shift)
Core Web VitalsCumulative Layout Shift measures visual instability — how much page elements unexpectedly move while the page is loading.
INP (Interaction to Next Paint)
Core Web VitalsInteraction to Next Paint measures the responsiveness of your page to user interactions — clicks, taps, and keyboard input.
Core Web Vitals
Core Web VitalsCore Web Vitals are Google's set of user experience metrics that measure loading performance (LCP), visual stability (CLS), and interactivity (INP).
Shopify Speed Report
ShopifyShopify's built-in Speed Report (Online Store > Themes > View Report) shows your store's Lighthouse performance score relative to similar Shopify stores, along with factors affecting your score.
Check your store's Google PageSpeed Insights with our free tools
Get a full audit across all 6 performance categories — including performance — in under 60 seconds.
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