Definition
PageSpeed Insights (PSI) is a free Google tool that evaluates a web page's loading performance and provides optimization recommendations. The tool assigns a score from 0 to 100 based on Google's Core Web Vitals metrics, including Largest Contentful Paint (LCP), First Input Delay (FID) replaced by Interaction to Next Paint (INP), and Cumulative Layout Shift (CLS). PSI combines lab data (simulated via Lighthouse) and field data (real Chrome user data via the Chrome UX Report). Loading speed is an official Google ranking factor, making this tool essential for any technical SEO work. PageSpeed Insights provides concrete, prioritized recommendations for improving performance, such as image optimization, JavaScript reduction, and caching.
Key Points
- Official Google tool measuring Core Web Vitals, confirmed ranking factors
- Combines lab data and real Chrome user data
- Provides concrete, prioritized recommendations for improving performance
Practical Examples
Performance audit before an SEO campaign
Before launching a link building campaign, test your target pages in PageSpeed Insights. A low score can negate the positive effect of acquired backlinks, as Google penalizes slow pages in rankings.
Competitor comparison
Test your competitors' pages in PageSpeed Insights to identify whether speed is a competitive advantage you can exploit or a gap you need to close.
Frequently Asked Questions
Google considers a score of 90-100 as good (green), 50-89 as needing improvement (orange), and below 50 as poor (red). In practice, most sites score between 40 and 70 on mobile. A mobile score of 70+ is already competitive, but aiming for 90+ is recommended to maximize SEO impact.
Google confirms that loading speed is a ranking factor, but it is one factor among hundreds. The Core Web Vitals measured by PSI impact ranking, but quality content and relevant backlinks remain more decisive factors. Speed becomes especially critical when two pages are of equivalent quality.
Go Further with LemmiLink
Discover how LemmiLink can help you put these SEO concepts into practice.
Last updated: 2026-02-07