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Performance Review

What is a Performance Audit?

A performance audit is a systematic analysis of website performance with the goal of optimizing Load Speed and improving user experience. Since Google has been using Core Web Vitals as a ranking factor since 2021, a performance audit is essential for successful SEO.

Performance Impact

Studies show: 1 second loading time delay reduces conversions by 7%

Why is Performance Important for SEO?

1. Core Web Vitals as Ranking Factor

Google has been using Core Web Vitals as a direct ranking factor since 2021:

  • Largest Contentful Paint (LCP): < 2.5 seconds
  • First Input Delay (FID): < 100 milliseconds
  • Cumulative Layout Shift (CLS): < 0.1

2. User Experience Signals

Performance directly influences important UX metrics:

  • Exit Rate
  • Visit Length
  • Pages per Session
  • Conversion Rate

3. Crawl Budget Refinement

Fast websites are crawled more frequently and efficiently.

Performance Audit Checklist

Phase 1: Initial Analysis

001. Identify Tools and Metrics

  • Google PageSpeed Insights
  • Google Search Console Core Web Vitals
  • GTmetrix
  • WebPageTest
  • Chrome DevTools

002. Capture Baseline Metrics

  • Current LCP, FID, CLS values
  • Page Speed Score (Mobile & Desktop)
  • Time to First Byte (TTFB)
  • First Contentful Paint (FCP)

003. Page Prioritization

  • Top traffic pages
  • Conversion-critical pages
  • Pages with poor performance

Phase 2: Detailed Analysis

001. Core Web Vitals Deep-Dive

Metric
Good
Needs Improvement
Poor
LCP
≤ 2.5s
2.5s - 4.0s
> 4.0s
FID
≤ 100ms
100ms - 300ms
> 300ms
CLS
≤ 0.1
0.1 - 0.25
> 0.25

002. Resource Analysis

  • JavaScript Collection size
  • CSS files size
  • Image optimization
  • Font loading
  • Third-party scripts

003. Server Performance

  • TTFB analysis
  • CDN usage
  • Caching strategies
  • Server response codes

Phase 3: Problem Identification

001. Common Performance Issues

Identify Performance Problems

  • Unoptimized images (WebP, AVIF)
  • Render-blocking JavaScript
  • Non-critical CSS in head
  • Missing compression
  • Inefficient font loading
  • Third-party scripts without optimization
  • Missing browser caching headers
  • Large JavaScript bundles
  • Unnecessary HTTP requests
  • Missing resource hints

002. Mobile-Specific Issues

  • Touch target size
  • Viewport configuration
  • Mobile-specific loading times
  • Progressive Web App features

Phase 4: Optimization Strategies

001. Quick Wins (Immediately Implementable)

Optimization
Impact
Effort
Priority
Image optimization
High
Low
1
Gzip compression
High
Low
1
Browser caching
Medium
Low
2
CSS minification
Medium
Low
2
JavaScript optimization
High
High
3

002. Technical Optimizations

Performance Optimization

6 steps from analysis to Tracking:

  1. Conduct audit
  2. Identify problems
  3. Set priorities
  4. Implement optimizations
  5. Testing
  6. Monitoring

003. Content Delivery Optimization

  • CDN implementation
  • Edge caching
  • Image CDN
  • Critical CSS
  • Resource hints (preload, prefetch, preconnect)

Phase 5: Monitoring and Reporting

001. Performance Monitoring Setup

Performance Metrics

Continuous monitoring of:

  • Core Web Vitals (Real User Monitoring)
  • Page Speed Scores
  • Conversion Impact
  • Crawl Efficiency

002. Reporting Structure

Performance Status

  • Core Web Vitals trend
  • Top performance problems
  • Optimization ROI
  • Mobile vs. Desktop performance

Tools for Performance Audits

1. Google Tools

  • PageSpeed Insights: Lab data and field data
  • Search Console: Core Web Vitals report
  • Chrome DevTools: Detailed analysis
  • Lighthouse: Automated audits

2. Third-Party Tools

  • GTmetrix: Comprehensive performance analysis
  • WebPageTest: Detailed waterfall analysis
  • Pingdom: Monitoring and alerting
  • New Relic: Application Performance Monitoring

3. Specialized Tools

  • Screaming Frog: Technical SEO + Performance
  • SEMrush: Site audit with performance
  • Ahrefs: Site audit tool

Performance Audit Best Practices

001. Conduct Regular Audits

  • Weekly: Core Web Vitals monitoring
  • Monthly: Complete performance audit
  • For major changes: Immediate audit

002. Mobile-First Approach

  • Mobile performance has priority
  • Progressive enhancement
  • Touch-optimized interactions

003. Real User Monitoring (RUM)

  • Field data is more important than lab data
  • Test various devices and connections
  • Consider geographical distribution

004. Define Performance Budget

  • Maximum allowed bundle size
  • Loading time goals per page type
  • Core Web Vitals thresholds

Common Performance Audit Mistakes

Performance Audit Pitfalls

  • Only considering lab data (ignoring field data)
  • Neglecting mobile performance
  • Not considering third-party scripts
  • Not measuring after optimization
  • Not defining performance budget

ROI of Performance Optimizations

Performance ROI

  • 1 second loading time improvement = 7% conversion increase
  • 0.1 CLS improvement = 15% less bounce rate
  • 100ms FID improvement = 1% more revenue

Related Topics

Last Update: 28. September 2025