The technical SEO fundamentals every developer should implement — from meta tags to structured data to Core Web Vitals.
SEO Is Not Magic
Technical SEO is about making your content easy for search engines to find, crawl, and understand. Most of it is straightforward HTML and server configuration.
Essential Meta Tags
Every page needs:
— unique, under 60 characters, includes target keyword— under 155 characters, compelling summary— prevents duplicate content issues- Open Graph tags for social sharing
Semantic HTML Structure
Search engines understand semantic markup:
- One
per page — your main topic throughin logical hierarchyfor main contentfor navigationfor dates withdatetimeattribute
Sitemap and Robots
Generate sitemap.xml automatically. Include all public pages with last-modified dates. The robots.txt should point to your sitemap and allow crawling of important pages.
Core Web Vitals
Google uses these metrics for ranking:
- LCP (Largest Contentful Paint): under 2.5s — optimize images and server response time
- CLS (Cumulative Layout Shift): under 0.1 — set image dimensions, avoid dynamic content injection
- INP (Interaction to Next Paint): under 200ms — keep main thread fast
Page Speed
- Compress images (WebP/AVIF)
- Enable gzip/brotli compression
- Use CDN for static assets
- Minimize JavaScript bundles
- Lazy load below-the-fold content
Internal Linking
Link between related pages with descriptive anchor text. This helps search engines understand your site structure and passes authority between pages.
Structured Data
JSON-LD structured data helps Google show rich results:
- Article schema for blog posts
- FAQ schema for frequently asked questions
- Product schema for e-commerce
- BreadcrumbList for navigation paths
Mobile-First
Google indexes the mobile version of your site first. Ensure your mobile experience is not a degraded version of desktop. Same content, same internal links, responsive layout.
Common Mistakes
- Blocking CSS/JS in robots.txt (Google needs to render your page)
- Using JavaScript rendering without SSR (search engines struggle with client-only rendering)
- Duplicate content across multiple URLs
- Missing alt text on important images
- Slow server response time (TTFB over 600ms)