Key Ranking Factors

Google uses hundreds of ranking factors, but as a developer, you can directly influence many of them. Let's focus on the factors within your control.

Content Quality

Search engines prioritize content that:

• Answers the user's query comprehensively
• Is original and provides unique value
• Is well-structured with clear headings
• Is regularly updated when appropriate

E-E-A-T: Experience, Expertise, Authority, Trust

Google evaluates content quality through E-E-A-T:

• Experience - First-hand experience with the topic
• Expertise - Demonstrated knowledge
• Authority - Recognition from others in the field
• Trust - Accurate, honest, safe content

Technical Health

Your site should:

• Load quickly (Core Web Vitals)
• Be mobile-responsive
• Use HTTPS
• Have no broken links or errors
• Be easily crawlable

Technical SEO Checklist

• SSL/HTTPS enabled
• Mobile-responsive
• No broken links (404s)
• Fast load times
• Valid HTML
• Accessible content

On-Page SEO

Each page should have:

• A unique, descriptive title tag
• A compelling meta description
• Proper heading hierarchy (H1, H2, H3)
• Descriptive URLs
• Internal links to related content

Heading Hierarchy Example

<h1>SEO Guide for Next.js</h1>         <!-- One per page -->
  <h2>Understanding Metadata</h2>       <!-- Main sections -->
    <h3>Title Tags</h3>                  <!-- Subsections -->
    <h3>Meta Descriptions</h3>
  <h2>Technical SEO</h2>
    <h3>Sitemaps</h3>
    <h3>robots.txt</h3>

User Experience Signals

Google measures user experience through:

• Largest Contentful Paint (LCP) - Loading performance
• Interaction to Next Paint (INP) - Responsiveness
• Cumulative Layout Shift (CLS) - Visual stability

Core Web Vitals Targets

Metric	Good	Needs Improvement	Poor
LCP	< 2.5s	2.5s - 4s	> 4s
INP	< 200ms	200ms - 500ms	> 500ms
CLS	< 0.1	0.1 - 0.25	> 0.25

Mobile-First Indexing

Google primarily uses the mobile version of your site for indexing and ranking. This means:

• Mobile experience is critical
• Content should be identical on mobile and desktop
• Ensure touch targets are adequate (48px minimum)
• Avoid horizontal scrolling

Backlinks

While you can't directly control backlinks, you can:

• Create link-worthy content
• Make it easy for others to reference your content
• Build relationships in your industry
• Guest post on relevant sites

Page Speed

Speed affects both rankings and user experience:

// Good: Server Component with fast data fetching
export default async function Page() {
  const data = await getCachedData() // Cached/fast
  return <div>{data.content}</div>
}

// Bad: Client-side fetch causing loading states
'use client'
export default function Page() {
  const [data, setData] = useState(null)
  useEffect(() => {
    fetch('/api/data').then(r => r.json()).then(setData)
  }, [])
  return <div>{data?.content || 'Loading...'}</div>
}

SEO Audit Checklist

Before we dive into implementation, here's a quick audit checklist:

• Every page has a unique title
• Every page has a meta description
• URLs are descriptive and clean
• Site uses HTTPS
• Site is mobile-responsive
• No broken links (404s)
• Images have alt text
• Site has a sitemap
• robots.txt is configured correctly
• Core Web Vitals pass

Summary

In this lesson, you learned:

• Content quality and E-E-A-T principles
• Technical health requirements
• On-page SEO elements
• Core Web Vitals and their targets
• The importance of mobile-first design
• How page speed affects rankings

In the next lesson, we'll develop the SEO mindset every developer needs.