PageSpeed Insights
PerformanceGoogle's Core Web Vitals and performance analysis tool
Overview
PageSpeed Insights stands as Google's official performance analysis tool, providing the definitive measurement of Core Web Vitals that directly impact search rankings. Built around Google's Lighthouse auditing engine and Chrome User Experience Report (CrUX) data, PSI offers both controlled lab testing and real-world field performance metrics. The tool became essential for SEO practitioners after Google's 2021 Page Experience update made Core Web Vitals confirmed ranking factors.
Unlike third-party performance tools that simulate various conditions, PageSpeed Insights uses actual data from Chrome browsers visiting your site. This makes its scores the most accurate predictor of how Google evaluates your page performance for ranking purposes. The tool analyzes three core metrics: Largest Contentful Paint (loading), First Input Delay (interactivity), and Cumulative Layout Shift (visual stability).
Google launched PSI in its current form in 2018, replacing the previous version with Lighthouse-powered analysis and real user metrics. The tool reflects Google's broader push toward user experience as a ranking factor, giving SEOs direct insight into performance metrics that matter for search visibility.
Key features
Core Web Vitals Analysis
Measures LCP, FID, and CLS metrics using real user data from Chrome User Experience Report. Provides pass/fail scores that directly impact Google search rankings.
Lab vs Field Data
Combines controlled lab testing with 28-day real user metrics from CrUX database. Shows both theoretical performance and actual user experience across different devices.
Mobile and Desktop Testing
Separate performance audits for mobile and desktop versions with device-specific recommendations. Mobile scores typically carry more weight for SEO rankings.
Lighthouse Integration
Powered by Google's Lighthouse engine providing detailed performance, accessibility, and SEO audits. Offers specific technical recommendations with estimated impact.
Origin-Level Insights
Aggregated performance data for entire domains, not just individual pages. Useful for understanding site-wide performance trends and identifying systemic issues.
API Access
Programmatic access to performance data for automated monitoring and integration with other tools. Supports bulk analysis and historical tracking.
Pricing
| Plan | Price | Includes |
|---|---|---|
| Free | $0 | Unlimited URL analysis, Core Web Vitals data, optimization suggestions, field and lab data |
FAQ
How often should I check PageSpeed Insights for my website?
Check monthly for established sites or after any significant changes to page structure, images, or scripts. Core Web Vitals data updates every 28 days, so more frequent checks won't show meaningful changes in field data.
Why do PageSpeed Insights scores differ from other performance tools?
PSI uses real user data from Chrome browsers while other tools often simulate different network conditions or devices. PSI scores directly correlate with Google's ranking algorithms, making them more relevant for SEO.
What's the difference between lab and field data in PageSpeed Insights?
Lab data is controlled testing simulating a slow 4G connection on a mid-tier mobile device. Field data comes from actual Chrome users visiting your site over 28 days, providing real-world performance metrics.
Can I improve my PageSpeed Insights score without a developer?
Basic improvements like image compression and caching plugins can help, but meaningful gains usually require technical changes to code, hosting, or CDN configuration. WordPress users can achieve moderate improvements with optimization plugins.
Do PageSpeed Insights scores directly affect Google rankings?
Yes, Core Web Vitals are confirmed ranking factors as part of Google's Page Experience update. However, they're one of hundreds of factors, and great content can still rank well with moderate performance scores.
How does PageSpeed Insights compare?
View all comparisons →Review Sentiment
Bottom line
PageSpeed Insights is free and worth exploring for web developers — official Google tool providing both lab and field Core Web Vitals data. Still too new for formal reviews, so set expectations accordingly.
People love
- +Official Google tool providing both lab and field Core Web Vitals data
- +Free with no account required — instant performance analysis for any URL
- +Combines Lighthouse audit scores with Chrome User Experience Report (CrUX) field data
Common complaints
- –Lab scores can differ significantly from real user experience field data
- –No historical tracking — shows only current snapshot without trend analysis
- –Recommendations can be overly technical for non-developer site owners
Last updated Feb 2026