If technical SEO is about whether search engines can reach your pages, on-page SEO is about what they find when they get there. It’s everything you control on the page itself: what it says, how it’s structured, and the signals in its HTML.
The main elements
Content that matches intent. The page fully answers what the searcher wants, in the format they expect (see search intent). This matters more than any tag.
Title tag. The clickable headline in search results, including the main topic (see title tag).
Meta description. The summary under the title, written to earn the click.
Headings. One clear H1, with H2s and H3s that break the content into logical sections (see header tags).
URL. Short, readable and descriptive: /drain-cleaning/ rather than /page?id=482.
Images. Compressed files, descriptive file names and useful alt text.
Internal links. Links to and from related pages with descriptive anchor text (see internal link).
Structured data. Schema markup describing the page’s main subject.
Trust signals. Author names, dates, contact details, reviews and evidence where they matter.
Why it matters
On-page SEO is the most direct lever you have. You can’t control who links to you or what Google changes, but you can rewrite a page today.
Coastline Plumbing’s water heater page was titled “Services”, had no H1, opened with three paragraphs about the company’s history, and only mentioned water heaters in a bulleted list near the bottom. After a rewrite (title “Water Heater Repair and Installation in Austin | Coastline Plumbing”, an H1 matching it, an opening that states prices and same-day availability, sections on common problems, tank versus tankless, and a clear phone number), it moved from page three to the top five for its main terms within two months.
A quick checklist for any page
- Is there one clear topic, matching a real search?
- Does the title include it, and give a reason to click?
- Does the H1 confirm it?
- Does the opening answer the main question or state the offer?
- Are related questions covered under clear headings?
- Do images have alt text, and are they compressed?
- Does the page link to related pages, and do they link back?
- Is there an obvious next step: call, book, buy?
Common mistakes
- Optimizing for keywords instead of for the reader
- Several pages targeting the same search
- Generic titles and missing descriptions
- Burying the important information below long introductions
How to check
Test individual pages with the free Meta Tag Checker. RankThat’s Site Audit checks titles, descriptions, headings, alt text, duplicate and thin content across the whole site, and on WordPress its AI fixes can draft improvements for your review.