Glossary

H1 tag

Page's main heading. Each page must have exactly one H1 containing the primary keyword.

Full definition

H1 tag is the main heading of a page. Strong on-page factor: helps search engines and users understand what the page is about.

Rules

•One H1 per page — this is axiomatic. Multiple H1s dilute the signal.
•Contains the main keyword — preferably up front
•Different from Title — Title is optimized for SERP, H1 for the user
•Logical, readable — not keyword-stuffed

Example

<!-- Title for SERP -->
<title>Free SEO Audit in 1–2 Days | Adaptive Lab</title>

<!-- H1 on the page -->
<h1>Free SEO Audit of Your Website in 24 Hours</h1>

H1 is more expansive, explains the value, and captures attention after the click.

Heading hierarchy

Proper structure:

H1 — main page heading (one)
  H2 — article section
    H3 — subsection
      H4 — details
  H2 — next section
    H3 — subsection

Don't skip levels. H1 → H3 without H2 — Google doesn't like it.

Top mistakes

1. Multiple H1s per page — common from poor CMS templates 2. H1 in the logo — logo shouldn't be H1; H1 = content heading 3. H1 as image — Google can't read text from images; needs alt text 4. Full duplication of Title — missed diversity opportunity 5. ALL CAPS — reduces readability, no SEO benefit

Check

Open page → View Source → Ctrl+F: `<h1` — should be one. Alternative: Screaming Frog → H1 tab.