What is On-Page SEO?

On-page SEO refers to any search engine optimization work you do on the page itself: the content and the HTML that delivers it. Because you control every one of these elements, on-page work is the part of SEO you can act on today, without waiting for other sites to link to you.

The main on-page SEO elements

Each element below is something you can check and fix one page at a time:

• Title tag: the clickable headline searchers see in results. About 60 characters is a practical guideline, not a limit: Moz's title tag guide (updated March 2025) estimates roughly 90% of titles that length display in full. The real cutoff is display width, and Google sometimes rewrites title links anyway, so a clear, descriptive title matters more than an exact count.
• Meta description: the snippet that often appears under your title in results. A specific, compelling one earns more clicks from the same ranking position.
• Headings: a main heading that names the topic, with subheadings nested in a logical order. A single H1 is a useful convention, not a ranking requirement: Google's John Mueller said in 2019 you can use H1 tags “as often as you want.” What actually hurts is a confusing heading order readers can't skim.
• Keyword placement: the target phrase in your title, main heading, and opening paragraph, worked in naturally.
• Internal links: links between your own pages with descriptive anchor text, so both readers and crawlers know what's on the other end.
• URL slug: short and descriptive, like /on-page-seo/ rather than /?p=123.
• Image filenames and alt attributes: name files for their content, then write alt text by the image's role. Informative images get a description, decorative ones get an empty alt attribute (alt=""), and linked images get their destination. Screen readers read alt text aloud, so this is accessibility work too.
• Schema markup: structured data that helps search engines understand the page and can earn richer result listings.

On-page SEO step by step

Work through one page at a time, in this order:

1. Match the page to one search intent. Search your target keyword and look at what ranks: if searchers want a how-to and you wrote a sales page, no title tweak will save it.
2. Write a keyword-led title tag and meta description. “Home | Acme” tells searchers nothing; “Handmade Leather Wallets | Acme” puts what the page offers in the first words.
3. Give the page a main heading that names the topic, then subheadings a reader could skim to find their answer.
4. Keep the URL slug short and descriptive.
5. Add internal links from your related pages, with anchor text that says where the link goes.
6. Name image files for their content and write alt text by role: describe what informative images show, say where linked images lead, and leave alt text empty (alt="") on decorative images. WebAIM's alternative text article walks through each case.

Start with the pages that already get impressions in Google Search Console. A better title on a page ranking 11th moves faster than a brand-new post starting from zero.

Common on-page SEO mistakes

Keyword stuffing is the classic: repeating the target phrase until the copy reads as spam to readers and ranking systems alike. Write for the reader and let the keyword land where it naturally would. Duplicate or missing title tags are nearly as common; pages end up competing with each other in results or showing an auto-generated title nobody clicks. And several thin pages chasing the same keyword usually hold each other back, so consolidate them into one page that fully answers the question.

On-page vs. off-page vs. technical SEO

SEO work splits into three buckets, sorted by where the work happens:

• On-page SEO: the content and HTML on pages you control, including copy, title tags, headings, internal links, and images.
• Off-page SEO: ranking signals that happen outside your own website, such as backlinks earned through guest blogging, brand mentions, and reviews. You can influence these, but you can't control them.
• Technical SEO: how reliably search engines can crawl, render, and index your site, covering crawlability, indexing, site speed, and mobile-friendliness.

Site speed causes the most sorting confusion: current guides from Cloudflare and Semrush both file it under technical SEO, not on-page, and mobile-friendliness usually sits in the same bucket. The label matters less than the work, though. A slow page loses readers and rankings whichever list you put it on.

For a tactic-by-tactic comparison, see our guide On-Page vs. Off-Page SEO: Breaking Down Tactics That Actually Work.