On-page SEO

Title, description, canonical, structured data

The SEO signals you control inside the page itself — as opposed to off-page (backlinks). It’s what the HTML starter template already wires up; Open Graph handles the social-sharing side.

The `<head>` essentials

<title>Unique title, ≤ 60 characters</title>
<meta name="description" content="Persuasive summary, ≤ 160 characters." />
<link rel="canonical" href="https://site.com/page" />
<meta name="robots" content="index, follow" />

title — the most visible on-page factor (it becomes the blue link on Google). Unique per page, with the keyword near the start.
description — not a direct ranking factor, but the snippet text drives CTR. Write it like an ad.
canonical — points to the preferred URL when the same content lives at several addresses (with/without www, tracking params). Prevents duplicate content.
robots — noindex removes the page from the index; nofollow skips its links.

Semantic structure

Semantic HTML helps the crawler understand the hierarchy:

A single <h1> per page describing the main topic.
<h2>/<h3> in logical order, without skipping levels for looks.
Descriptive alt on every <img> — accessibility and image SEO.
Short, readable URLs (/blog/on-page-seo, not /p?id=42).

Structured data (JSON-LD)

Marks up the content in schema.org vocabulary and enables rich results (stars, breadcrumbs, FAQ). It goes in a <script> in the <head>:

<script type="application/ld+json">
  {
    "@context": "https://schema.org",
    "@type": "Article",
    "headline": "Article title",
    "datePublished": "2026-06-27",
    "author": { "@type": "Person", "name": "Name" }
  }
</script>

Multilingual sites: `hreflang`

Each language is a URL, linked via hreflang so Google serves the right version — see i18n on the web. Always include the x-default tag.

Quick checklist

[ ] Unique title ≤ 60 and description ≤ 160.
[ ] canonical pointing to the preferred URL.
[ ] One <h1> and a coherent heading hierarchy.
[ ] alt on every image.
[ ] JSON-LD for the content type.
[ ] sitemap.xml and robots.txt published.

Related: Open Graph · HTML starter template.