Zerply
Technical SEO

Page Speed

Definition

How quickly a web page loads and becomes interactive for users. A confirmed Google ranking factor and critical component of user experience, especially on mobile devices.

Why It Matters

Page speed directly impacts rankings, user experience, and conversions. Google uses page speed as a ranking factor for both desktop and mobile searches. Studies show 1-second delays reduce conversions by 7%, and 53% of mobile users abandon sites taking over 3 seconds to load.

How It Works

Page speed is measured through various metrics: Largest Contentful Paint (LCP), First Input Delay (FID), and Cumulative Layout Shift (CLS) - collectively known as Core Web Vitals. Slow sites are penalized in rankings, while fast sites may receive ranking boosts. Speed impacts crawl budget, user engagement signals, and overall site performance.

Use Cases

  • An e-commerce site optimizes images and reduces JavaScript to improve page speed from 5.2s to 1.8s, increasing conversions by 32%
  • A news site implements lazy loading and CDN to handle traffic spikes without performance degradation
  • A blog compresses images and enables browser caching, improving mobile page speed score from 45 to 92

Best Practices

  • Optimize and compress images - use WebP format and appropriate sizing for displays
  • Minimize JavaScript and CSS - remove unused code and defer non-critical scripts
  • Use a Content Delivery Network (CDN) to serve content from servers closer to users
  • Enable browser caching to store static resources locally
  • Implement lazy loading for images and videos below the fold
  • Monitor Core Web Vitals monthly and prioritize fixes for pages with poor scores

Frequently Asked Questions

Why is Page Speed important for SEO? +
Page speed is a confirmed Google ranking factor impacting both desktop and mobile rankings. Slow sites hurt rankings, conversions (7% loss per second delay), and user experience. 53% of mobile users abandon sites over 3 seconds.
How is Page Speed measured? +
Page speed is measured through Core Web Vitals: Largest Contentful Paint (LCP), First Input Delay (FID), and Cumulative Layout Shift (CLS). These metrics assess loading performance, interactivity, and visual stability.
What's a good page speed score? +
Aim for LCP under 2.5 seconds, FID under 100 milliseconds, and CLS under 0.1. Google PageSpeed Insights scores pages 0-100, with 90+ being excellent, 50-89 needing improvement, and below 50 requiring urgent fixes.

Related Terms

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