SEO On Page: What It Is, the Key Factors and How to Check

Key takeaways

On-page SEO covers what you control on each page: title, meta description, headings, content, URL, images, internal links and structured data.
The content itself matters most. The tags help Google understand a page that already answers the search well.
Off-page SEO is what happens elsewhere: links, mentions and reviews. Technical SEO is the site underneath. You need all three.
Google says it ignores the meta keywords tag and that word count alone does not affect rankings.

8on-page factors worth checking on every important page

0weight Google gives the meta keywords tag

3M+products across the 18 US online stores whose SEO I supervise

What is on-page SEO?

On-page SEO is the work done on a page itself so Google and visitors understand what it is about and find it useful. It covers the title, meta description, headings, main content, URL, images, internal links and structured data. It is different from off-page SEO, which happens on other sites, and from technical SEO, which covers the whole site.

The SEO on page factors are the part of SEO you can change today, with no one else's permission. That is why it is one of the first things I review in an SEO audit: a page that is hard to understand will struggle, however strong the rest of the site is. If you want the bigger picture first, read what SEO is.

What are the main on-page SEO factors?

The main on-page factors are the main content, the title element, the meta description, the headings, the URL, image alt text, internal links and structured data. Content carries the most weight, because Google ranks pages that help people. The other factors help Google understand that content and help searchers choose your result.

Factor	What Google says	Problem I often find
Main content	Should be helpful, reliable and made for people	Thin service pages copied from a supplier
Title element	Unique, clear, concise and descriptive	Same title on dozens of pages
Meta description	Short, unique to the page, with the key points	Empty, or a list of keywords
Headings	Help readers scan; order is not critical for Google	No headings, or headings that say nothing
URL	Words that are useful for users	Random IDs and parameters
Image alt text	Short, descriptive, explains the image	Missing, or the file name
Internal links	Crawlable links with descriptive anchor text	Key pages with no links pointing to them
Structured data	Helps Google understand the page and can enable rich results	Markup that does not match the visible page

The sources behind that table are Google's SEO Starter Guide, its pages on title links, snippets and meta descriptions, link best practices and structured data, and its guide to helpful content.

Two details surprise most owners. First, Google can build the blue title link from several sources, not only your title tag, including the main heading and the anchor text of links to the page. Second, Google mainly builds the snippet under the title from the page content itself and uses the meta description when it describes the page better. Both are reasons to make the visible page clear, not just the tags.

What is the difference between on-page and off-page SEO?

On-page SEO is what you change on your own pages: content, titles, headings and internal links. Off-page SEO is what happens elsewhere and points back to you: links from other sites, mentions, reviews and your Google Business Profile. Technical SEO is the base that lets Google crawl and index both. A page needs all three.

	On-page	Off-page	Technical
Where	On the page	On other sites and platforms	Across the whole site
Examples	Title, content, headings, internal links	Links, mentions, reviews	Crawling, indexing, speed, redirects
Who controls it	You, fully	You influence it, others decide	You and your developer
Read more	This guide	Off-page SEO	What is technical SEO

Which on-page SEO rules can you ignore?

Several old rules no longer matter, according to Google's own starter guide. Google does not use the meta keywords tag. Content length alone does not affect ranking. Heading order and the number of headings are not critical. Keywords in the domain or URL have hardly any effect. Spend that time on making the page more useful instead.

The same guide warns against keyword stuffing: repeating the same words, even in variations, tires readers and does not help. When a proposal promises "keyword density" targets or a fixed word count, ask what problem it solves for your customers.

How to check the on-page SEO of a page in 20 minutes

Find the search the page should win. In Search Console, open the page in the Performance report and look at the queries. Does the page match them?
Read the title and meta description as a buyer would in the results. Do they say what the page offers and why to click?
Read the first paragraph. It should answer the main question or state the offer right away.
Scan the headings. Can someone understand the page from the headings alone?
Check the images. Are they real, compressed and described with alt text?
Look at the links. Does the page link to related services, and do other pages on your site link to it?
Compare with the top results. What do they answer that your page does not?

On large sites the same check happens at template level. Across the 18 US online stores I supervise, with more than 3 million products, nobody writes millions of titles by hand: we fix the templates that generate them, then review samples by category. For a full technical pass, use the technical SEO checklist.

When does a business need an on-page SEO audit?

You need one when pages get impressions but few clicks, when important pages rank on page two, after a redesign or when several pages seem to compete for the same search. An audit reviews every important page against these factors and gives you a list of fixes in order of impact, so you are not guessing.

On-page review is part of every SEO audit I do, and audits start at $450. If your pages need rewriting rather than tuning, that is SEO content writing. To plan the work across the site, read how to build an SEO strategy, or book the free 30-minute diagnosis from the home page.

Frequently asked questions

Is on-page SEO more important than off-page SEO?

Neither works alone. On-page comes first because it is fully in your control, and links rarely rescue a page that does not answer the search.

How long should a page be for SEO?

As long as it needs to answer the question well. Google says length alone does not matter for ranking.

Should every page have an H1?

It is good practice to have one clear main heading. Google uses it, among other signals, to understand the page and build the title link.

Does Google rewrite my titles?

Sometimes. It can use headings, other text on the page or link text when it thinks your title does not describe the page well.

Can a plugin like Yoast or Rank Math do on-page SEO for me?

It helps you fill in titles, descriptions and markup. It cannot decide which search a page should target or write content that answers it.

About the author

Juan José Giraldo is an SEO consultant in Medellín, Colombia, with 5+ years of experience. He works on technical and local SEO for 600+ US car dealerships at Reunion Marketing, an Inc. 5000 agency, and supervises the SEO of 18 US online stores with more than 3 million products at Prontomowers. Read more · LinkedIn.

SEO on page: the factors Google reads on every page.