On-Page SEO: A Complete Checklist for Every Page

On-page SEO is the set of adjustments made inside each page, such as title, description, headings, URL, text, images, links and structured data, so that Google understands the subject and the reader finds the answer fast. Order matters: intent and content first, HTML elements after. Below is the checklist, from what weighs the most to what needs the most polish.

This guide goes deeper into the content layer of the complete SEO guide. It assumes you have already chosen the page's main keyword. If you have not, start with keyword research.

Quick summary

• What weighs the most in on-page SEO is the page answering the search intent fully and right at the start. HTML elements help, but they do not save weak content.
• Title and description are, largely, your storefront in the results: Google may rewrite them, but it starts from a good base.
• There is no magic length for a title, description or text. Google truncates according to the device width.
• A short, descriptive URL, headings that form a logical outline, images with alt text and internal links with clear anchors complete the base.
• Structured data (JSON-LD) is optional, must reflect what is visible and does not guarantee a special display.
• Prioritize: 1) intent and content, 2) title and H1, 3) structure and links, 4) media, 5) schema.

How to read this guide: if you are building your first page, follow the checklist in order and copy the template. If you already optimize pages, go to the priority tables, the "For SEO professionals" blocks and the JSON-LD example.

What is the order of priority in on-page SEO?

Prioritize by effect and effort: content and intent first, then title and H1, then structure and links, then images and, last, structured data. The table shows why the order makes sense.

Priority	Item	Why it matters	Effort
1	Page intent and content	Defines whether the page deserves to appear for the search	High
2	Title and H1	Tell Google and the reader what the page is about; the title affects the click	Low
3	Structure (H2 and H3) and first paragraph	Makes reading and answer extraction easier	Medium
4	Internal links and anchors	Connect the page to the rest of the site	Medium
5	URL and meta description	Clarity and click-through rate; the description is a possible source of the snippet	Low
6	Images, alt text and video	Context, accessibility and image search	Medium
7	Structured data	Eligibility for rich results	Medium

In plain English: think of the page as a store. The content is what it sells, the title is the sign on the door, the description is the poster in the window, the headings are the aisle signs and the internal links are the arrows that lead to other sections. Nobody returns to a beautiful store that does not have the product they were looking for.

What does Google say about each element?

According to the official guidance, the central points are: unique and descriptive titles, descriptions that summarize the page, readable URLs, logical headings (without a rigid requirement), descriptive alt text, clear anchors and helpful content written for people. Google's SEO Starter Guide gathers these recommendations, and the sections below detail each one.

A warning from the same guide saves time: the keywords meta tag is ignored, there is no magic word count and repeating the keyword excessively violates the spam policies.

How do you write the title (the page title)?

Write a unique title that describes the page clearly and concisely, with the main keyword near the beginning and without repeating the same term several times. According to the title links documentation, Google does not set a character limit, but it truncates the title according to the device width.

A practical rule, ours and not Google's, is to aim for around 50 to 60 characters to reduce cutoffs. The brand name can go at the beginning or the end, separated by a delimiter, without repeating it in every sentence.

In plain English: the title is the name on the spine of the book on the shelf. Someone walking down the aisle decides in a second whether to pick it up. A clear, honest name earns more clicks than a list of loose words.

Google also rewrites titles it considers problematic: outdated, vague, in another language or with repetitive text across pages. If your title shows up differently in the results, check whether it fits any of those situations before trying to "force" the original.

For SEO professionals: to measure the effect of a title change, compare the CTR of the page's main queries in the Search Console performance report across equivalent periods before and after, changing one element at a time. Average position also varies, so CTR alone is misleading. Google may display a rewritten title, and manually inspecting the results page shows what actually appeared.

How do you write the meta description?

Write a one- or two-sentence summary that says what the person finds on the page and why it is worth clicking. According to the snippets documentation, snippets are created automatically from the page content, and Google uses the meta description when it describes the page better than the text does. There is no length limit, but the snippet is cut according to the device width.

That is why the description is an invitation to click, not a field for keywords. Use unique descriptions per page and leave automation only for large sites, with a well-thought-out template.

To compare options at the right length, Contentor's free SEO title and meta description generator writes 5 titles, a slug and a description and shows a Google preview.

How do you use H1, H2 and H3?

The H1 is the page's visible title (normally one per page), and the H2s and H3s form the sections and subsections, like a table of contents. Google's guidance says that semantic order helps screen readers, that Google does not penalize headings out of order and that there is no ideal number of headings.

Practical application: use H2s in question form when it makes sense ("How to...?", "How much does... cost?") and answer in the first paragraph right below. This helps the reader looking for a specific section and makes answer extraction easier. See more in content structure that LLMs can cite.

How do you define the URL?

Use short, readable URLs that describe the content. The URL structure documentation recommends descriptive words instead of ID numbers, hyphens instead of underscores to separate words and a single letter-case pattern, since URLs are case-sensitive. Avoid session IDs and unnecessary parameters.

After publishing, avoid changing the URL. If it is unavoidable, use a permanent redirect (301) from the old one to the new one.

How do you optimize images?

Use sharp images near the related text, with descriptive alt text and a meaningful file name. The images documentation calls alt text the most important attribute for giving an image metadata, advises describing the content instead of stacking keywords, recommends names like black-kitten-cat.jpg instead of IMG00023.JPG and states that formats such as JPEG, PNG, WebP, SVG and AVIF are supported.

Two technical details: Google does not index images inserted as a CSS background (use the <img> element), and heavy images worsen the experience. For speed, see Core Web Vitals.

How do you handle internal and external links?

Use anchors that describe the destination (for example, "SEO audit checklist") and avoid "click here". Internal links connect the page to the rest of the site and help the reader and Google discover related content. The guide to internal links has rules for quantity and anchors.

External links to trustworthy sources add credibility. Use rel="sponsored" on paid links and rel="ugc" on user-generated links, such as comments.

Do I need to use structured data?

It is not mandatory, but it helps make the content explicit and opens eligibility for rich results. According to Google's introduction to structured data, the recommended format is JSON-LD, the data must reflect what is visible on the page, and the documentation does not claim that schema improves ranking.

A minimal Article example, with dates and author (Google's documentation does not make any property mandatory):

{
  "@context": "https://schema.org",
  "@type": "Article",
  "headline": "How to choose your first guitar: a beginner's guide",
  "image": "https://www.example.com/images/beginner-guitar.webp",
  "datePublished": "2026-10-04T06:28:00Z",
  "dateModified": "2026-10-04T06:28:00Z",
  "author": {
    "@type": "Person",
    "name": "Author Name",
    "url": "https://www.example.com/author/name"
  }
}

For SEO professionals: validate with the Rich Results Test and keep parity between the JSON-LD and the visible content. Do not expect an FAQ rich result by default: Google's documentation states that it is only shown for well-known, authoritative government and health sites. The FAQ is still useful for the reader, just do not count on the visual. More on markup for AI in schema markup for AI Search. And update dateModified only after meaningful changes: Google lists changing the publication date without substantial change among the signals of content made for search engines rather than for people.

What is the complete checklist to copy?

The checklist below gathers 30 items, in priority order. Copy it into a spreadsheet or note and tick it off page by page. The "Before editing" items prevent rework.

BEFORE EDITING
[ ] The page has a defined main keyword and search intent
[ ] The intent matches the page format (guide, comparison, product)
[ ] No other page on the site has the same focus (cannibalization risk)
[ ] The page is indexable (no noindex, no robots.txt block)

CONTENT
[ ] The first paragraph answers the search question
[ ] Each section opens with the answer and then details it
[ ] Concrete examples, steps or data with a linked source
[ ] FAQ with real questions, when it makes sense
[ ] Technical terms explained the first time they appear
[ ] Author identified and update date visible
[ ] No claim without a source and no promise of results

HTML ELEMENTS
[ ] Unique, descriptive title with the main keyword near the beginning
[ ] Unique meta description summarizing the page
[ ] One H1 that matches the promise of the title
[ ] H2 and H3 form a logical outline (preferably in question form)
[ ] Short URL, with descriptive words and hyphens
[ ] Canonical points to the page itself (or to the preferred version)

IMAGES AND LINKS
[ ] Relevant, lightweight images inserted with <img>
[ ] Alt text describes the image without stacking keywords
[ ] Descriptive file names
[ ] 3 to 5 internal links with descriptive anchors
[ ] At least one incoming link from another page on the site
[ ] External links only to trustworthy sources, with the right rel when paid

STRUCTURED DATA AND TECHNICAL
[ ] JSON-LD consistent with the visible content, tested
[ ] The page works well on mobile
[ ] Main content present in the initial HTML (not dependent on a click)
[ ] Speed and stability checked

AFTER PUBLISHING
[ ] URL inspected in Search Console and indexing requested
[ ] Page included in the sitemap
[ ] Review scheduled for a few weeks out (impressions, clicks, position)

The four lines under "Structured data and technical" are a summary: the detail is in technical SEO for non-developers. To audit the whole site with the same logic, use the SEO audit step by step.

Hypothetical example: before and after a guitar page

Hypothetical example: an online guitar school has the page "How to choose your first guitar". The search is informational and comparative: beginners want to know what to look at before buying. The original page was published without review.

Element	Before	After
URL	/p?id=482&cat=3	/blog/how-to-choose-first-guitar
Title	Home - Guitar - Guitar lessons - Online guitar course - Rhythm School	How to Choose Your First Guitar: A Beginner's Guide - Rhythm School
Meta description	Guitar lessons, guitar course, online guitar, guitar for beginners	Nylon or steel? Size, string height and price range: see what to check before buying your first guitar.
H1	Guitar	How to choose your first guitar
Headings	None	Nylon or steel: which should you choose?, What size guitar is right for me?, How much should you spend on a first guitar?
Alt text of the main image	guitar guitar lesson	Hand comparing the neck of a nylon-string guitar and a steel-string one
Internal links	None	To the beginner course page and to a tuning guide

The first paragraph now carries the short answer ("For most beginners, a nylon-string, full-size guitar in a mid-range price bracket is the safest choice..."), and the rest goes into detail. Notice that the change involves no trick: the title stops being a list of terms and becomes a clear promise.

Frequently asked questions

What is on-page SEO?

It is the set of optimizations done inside the page itself so that Google understands the content and the reader finds what they are looking for: title, description, headings, URL, text, images, internal links and structured data. It complements technical SEO, which handles access to the site, and off-page SEO, which involves external signals.

What is the ideal length for the title and meta description?

Google does not set a character limit for either: it cuts according to the device width. As a practical rule, and not an official one, titles of 50 to 60 characters tend to show in full. Prioritize clarity and put the most important information at the start.

How many times should I repeat the keyword in the text?

There is no number. Use the main keyword in the title, the H1 and the first paragraph, naturally, and then vary with synonyms and related terms. Repeating terms excessively is keyword stuffing, a practice Google lists in its spam policies.

Can the H1 be different from the title?

It can. The title appears in the results and the browser tab, and the H1 is the heading inside the page. Ideally they promise the same thing, with similar words. Big differences confuse the reader and can lead Google to rewrite the displayed title.

Does alt text help SEO?

It helps in two ways: it gives Google context about the image and makes the page accessible to people who use screen readers. Google describes alt text as the most important attribute for image metadata. Describe what the image shows, without stuffing keywords.

Does structured data improve ranking?

Google's documentation does not claim that. Structured data makes the page eligible for rich results, when the data type supports it, and makes the content more explicit for machines. It must reflect what is visible and pass the validation test.

Next step

After adjusting the pages, the next step is the technical layer: read technical SEO for non-developers to make sure Google can access what you optimized. To master the choice of format before rewriting, review search intent. If you produce many pages, Contentor's article templates apply a validated structure (direct answer, headings, internal links) and publish to WordPress, and the final review is still yours: see how to generate articles with Contentor.

Read also:

• Internal links for SEO: a practical guide
• Content structure that LLMs can cite
• SEO audit step by step