How to do on page SEO in html website

On-page SEO for HTML websites starts with proper semantic HTML structure. Use heading tags hierarchically—one H1 per page that includes your primary keyword, followed by H2s and H3s that organize your content logically. Search engines use these tags to understand your page's structure and main topic. For a service page targeting "plumbing repair in Denver," your H1 might be "Emergency Plumbing Repair Services in Denver," with H2s breaking down service types. Beyond headings, ensure your title tag (the 50-60 character text in the browser tab) and meta description (155-160 characters) both include relevant keywords naturally and compel clicks from search results. These don't directly affect rankings as much as they once did, but they influence click-through rates, which does matter. Use semantic HTML elements like `<main>`, `<article>`, `<section>`, and `<aside>` instead of generic divs when appropriate—this helps search engines understand your content hierarchy.

Keyword optimization happens through strategic placement in your actual content. Include your target keyword in the first 100 words of your page, naturally throughout the body text (aim for 1-2% keyword density), and in at least one subheading. Internal linking is critical: link to other relevant pages on your site using descriptive anchor text that tells both users and search engines what the linked page is about. If you're writing about web design services, link to your portfolio or case studies with phrases like "view our web design portfolio" rather than generic "click here" links.

Image optimization often gets overlooked. Name your image files descriptively (use hyphens, not underscores) and always include alt text that describes the image and incorporates keywords where relevant. This helps with image search visibility and accessibility. For schema markup, implement structured data using JSON-LD format to mark up your business information, products, services, or articles. This helps search engines understand your content type and can earn you rich snippets in search results, improving visibility and click-through rates.

Finally, ensure your HTML is clean and valid. Slow page speed tanks rankings, so minimize render-blocking resources, compress images, and consider a CDN. Mobile responsiveness isn't just an on-page factor—it's fundamental. Your HTML must be responsive, and Core Web Vitals (loading speed, interaction responsiveness, visual stability) directly impact rankings now.