The 4 Pillars of SEO and How They Define Your Online Success

A company’s ability to grow through organic search no longer depends on tactical keyword usage or mechanical link-building. Growth is achieved when businesses invest in a search system built on four foundational pillars: Technical SEO, On-Page SEO, Content, and Off-Page Authority. When these elements reinforce each other, the result is not just higher rankings, but a predictable acquisition engine that supports revenue goals and scale.

Optimizing your website to be pleasing to both humans and robots is a complex endeavor. The best way to approach it is to break down your efforts across the 4 pillars of SEO – technical SEO, on-page SEO, content, and off-page SEO.

In this article, we’ll explain each of the 4 pillars of SEO and provide insights on how to best design your strategy.

How Search Works in a Nutshell

Before we delve into the specifics that define the 4 pillars of SEO, let’s first establish how search engines work. This will make the importance and standing of each element more evident and will allow us to put them into proper context.

To be able to deliver relevant content that matches the user’s query, search engines have bots (also called spiders, crawlers, and robots). Their task is to visit (crawl) all the pages that they can find on the internet.

Once they encounter a page, the bots check the content on it (including text, images, video, audio, etc.), and try to understand what it is about. The information is added to an index.

This database is similar to a library’s index where all the headlines are listed, together with information about the author, content, etc. However, Google’s index is a bit more complex.

First, a user keys a query into the search engine. Then, the search algorithm (the program that connects the user’s end and the index database) tries to identify the pages that best match their intent. The most relevant results with the best quality content are delivered as links in the search engine result pages (SERPs).

For businesses and website owners aiming to monitor their performance, a SERP rank tracker is an essential tool to keep track of keyword rankings, analyze competition, and optimize strategies to improve visibility.

However, modern search engines don’t only assess the quality and relevance of the content. They also take into account the technical aspects of the website. That’s because they don’t want to just provide answers, they want to deliver a great user experience.

All in all, by covering all the 4 pillars of SEO, you make sure you take into account three important factors. First, keep in mind that search robots can discover and understand your pages. Also, they deem you competent enough on the topic to show your content to the user. Last but not least, don’t forget that when a user lands on your website, they find exactly what they need.

The 4 Pillars of SEO

With that being said, let’s deconstruct each of the 4 pillars of SEO – technical SEO, on-page SEO, content, and off-page SEO.

1. Technical SEO: Makes Your Discoverable

Technical SEO ensures that your website can be properly crawled, indexed, and evaluated by search engines. Even world-class content is invisible without a discoverable and functional technical foundation. As of recent times though, this foundation is no longer limited to speed and mobile responsiveness; it must also support structured content that can be understood by AI-driven search systems.

Technical SEO focuses on managing indexing rules, optimizing crawl budgets, improving Core Web Vitals, securing user data through HTTPS standards, and building content architectures that connect related topics rather than isolating blog posts. With mobile-first indexing now fully adopted, search engines prioritize how your content behaves on smaller screens. Sites that load slowly, shift visually when scrolling, or fail to respect interaction signals lose trust quickly – both from users and ranking algorithms.

When taking care of technical SEO, consider the following factors:

Crawlability

The bots should have access to all of the pages you want them to crawl. If there are pages that you don’t want to be added to the index, you should list them in a robots.txt file. The bots may still crawl these pages, but they will not index them and show them in search results.

These can be service pages, pages with little, or low-quality content, duplicates, private pages, etc.

Also, large websites with more than 10K pages may reach the limits of their crawl budget and need to pay special attention to it.

Indexability

The best way to make sure the bots find and index all the pages you want them to is to create a sitemap. This is a list of the URLs of the pages, including information about the number of images on them and the date when the page was last modified/updated.

For WordPress websites, a sitemap can be generated by an SEO plugin, such as Yoast.

Mobile-Friendliness

Nowadays, the majority of content is consumed on mobile devices, as a result, search engines strive to provide users with pages that will look good on screens of all shapes and sizes.

In fact, Google has switched to mobile-first indexing. This means that, while websites that are desktop-only may not fall out of the search engine’s index, they are unlikely to be shown to users on mobile devices. This can, potentially, affect their overall ranking in a negative way.

There are different approaches to consider when making your website mobile-friendly, which one you choose depends on your needs.

Speed

Search engines favor websites that are quick and easy to access. Speed is among the most important page experience signals and for a reason.

Online users tend to have little patience for slow-loading websites and are likely to move on to the next link in the SERPs if the one they click on is taking too long to load. Therefore, when the algorithm decides what pages to provide the user, it’ll prioritize the faster ones.

In line with this, you should also optimize your core web vitals, a group of page experience signals that show the loading speed, interactivity, and visual stability of a page.

Website Structure

Website structure, also known as website information architecture, is the organization of pages on your website – the homepage, top-level pages, subpages, and so on.

There are different types of structures, but the flatter and easier to follow it is, the better search engines will find their way around your website.

Complex website structures can, potentially, confuse both the bots and your visitors and make them give up on trying to find what they are looking for.

2. On-Page SEO: Makes Your Pages Understandable

On-page SEO determines how clearly your content communicates meaning to search engines and how easily users can navigate and understand it. Modern engines evaluate a page based on semantic structure, user intent alignment, and topical context.

To achieve visibility, a page must first match the underlying reason for the search. Informational queries require educational content, commercial queries require comparison-oriented content, and transactional queries must provide straightforward pathways to action. When the content’s purpose does not match the user’s goal, search engines frequently remove the page from competitive rankings, regardless of its quality.

Effective on-page SEO now emphasizes clarity. Pages that perform well introduce their value immediately, often with summaries or highlight boxes that deliver upfront answers instead of forcing users to scroll. A clear table of contents helps both users and search engines understand page hierarchy, and an organized heading structure (H1-H3) communicates logic rather than stylistic preference. Semantic signals, such as related terms, entity names, and topic-specific vocabulary, guide search engines toward meaning without keyword repetition. Even images must contribute value, using alt text that clarifies their role rather than forcing irrelevant keywords.

On-page optimization is no longer a checklist; it has become a user-experience discipline. A well-structured page answers questions faster, helps users navigate intuitively, and encourages longer engagement. The result is a page that satisfies both algorithmic expectations and human needs, improving ranking potential and conversion opportunities simultaneously.

Here are the main factors we break down to take into account when optimizing your pages:

Page Title

The page should have a relevant title that is up to 70 characters. Also, make sure you optimize it with the main keywords you are targeting. If your title doesn’t correspond to the content on the page, the algorithm may generate a different one to display in the SERPs.

However, it’s a safe bet that you, as a human, can create a more compelling title, so avoid clickbait and think of something that is both engaging and accurate.

URL Slugs

The URL slug is the part of the link after the main domain and the category that is unique to each page on your website.

For example, in the URL https://devrix.com/tutorial/create-pillar-page/ “create-pillar-page” is the slug.

It’s best to avoid generic slugs that include only numbers and symbols, or are too general and consist of one or two words.

Descriptive URLs that feature the main keywords and parts of the headline are good for both SEO and UX.

Meta Description

Meta descriptions are a short summary of the content of the page that shows up in the SERPs under the page title and the link. The character limit here is 155.

If you don’t provide a description yourself, the search engine will generate an automatic one. It’s usually, the first 155 characters of the content on the page.

However, unique meta descriptions that make sense and include a call to action provide a better UX, and, as a result, improve SEO.

H-Tags

Breaking down the content on the page with H-tags provides better structure and readability. This makes it easier to understand not only by bots but by your visitors as well.

Search engines recognize these subheadings (as well as bullets and numbering). Among other things, bots can use H-tags to create special results such as featured snippets.

Keyword Optimization

Keywords allow you to better match your content with the user’s query and intent.

The main keywords that the page targets should be used in the headline, the subheadings, the meta description, the URL, and distributed across the text.

However, don’t overuse them because keyword stuffing not only sounds unnatural and is annoying, but it can cause a Google penalty.

Diversify the search terms you use with synonyms, keyword variations, and related keywords on relevant subtopics. This shows the bots that you are exploring different aspects of the topic and providing comprehensive information.

Image Alt Text

Alt text is used to describe the content of images.

In SEO, it has more than one benefit. It improves accessibility which shows you are providing a good user experience. On top of that, allows the bots to better understand what’s on your image.

In addition, in case there’s an issue with rendering the image, instead of blank space, the page may display the alt text and the image file name.

Internal Links

Internal links are very important in SEO. They strengthen your website structure. Also, internal links help the bots better understand the hierarchy and connection between your pages.

Furthermore, they distribute link equity. This means that the pages with high authority boost the less important ones that are linked to them.

Also, it’s not a secret that links and anchor text helps the bots “read” the pages better. This way they understand what your content is about, as well as discover new pages on your website.

When choosing the anchor text for internal links, optimize it with the main keyword of the target page. Alternatively, make it resemble a call to action that will help the user understand what to expect if they click.

Structured Data

Structured data and schema markup are among the most valuable assets in SEO.

Simply put, by marking up your pages, you provide search engines with organized information about the most important data they need to know about a page.

This minimizes the risk of the bots misunderstanding the purpose of the page and the content on it.

However, there’s more. The search algorithm uses structured data to create rich snippets. They are search results with additional information, images, review stars, prices, and other details that apply to the page.

These types of SERP links are highly clickable and can boost your traffic and engagement.

3. Content: Shows the Value You Provide

Content remains the most influential SEO pillar, written material alone is not enough to rank. As AI enables anyone to generate text, search engines are increasingly rewarding content that demonstrates real expertise, practical experience, and trustworthy perspectives. This shift places E-A-T (Expertise, Authoritativeness, and Trustworthiness) at the center of effective search strategies.

Modern content must show evidence of real knowledge. This can be expressed through industry examples, firsthand insights, validated sources, or case-supported claims. Content that simply summarizes public information reads like AI-generated text and offers no competitive value. Organizations that publish deep, experience-driven articles – especially those written or reviewed by subject matter experts – signal credibility that automated content cannot replicate.

Topical authority has also replaced isolated content production. Instead of publishing one-off articles, companies now build topic clusters, where one comprehensive pillar page serves as the central hub and multiple supporting articles expand related subtopics. This format mirrors how users research complex subjects and provides search engines with a clear hierarchy of expertise. A pillar page becomes the authoritative source, while its supporting content demonstrates depth.

Visuals, data, quotes, and schema markup further enhance content credibility. Search engines reward pages that enrich understanding through charts, tables, tutorials, expert commentary, or applied examples. The question today is not, “Did you write enough?” but, “Did you demonstrate expertise in a way that improves decision-making?”

EAT

Google’s page quality criteria documentation heavily focuses on three major aspects of high-quality content – expertise, authority, and trustworthiness.

Simply put, the content’s author and/or publisher needs to be a verified expert in their field with high authority, credibility, and respectability in the industry.

Furthermore, the website where the content is published has to provide transparent information on who’s behind it (be it a person, or company), and have a positive online reputation.

All this adds up to ensure that the information on the page is accurate, credible, and useful.

Relevance

The content should be relevant to the user’s query. This means that when you optimize for certain keywords, you need to provide information that matches them and is useful to the users who search them.

As mentioned, the content also needs to be aligned with the headline, otherwise, it will be considered misleading.

Exhaustiveness

More often than not, search engines favor long-form content. That’s because, if written well, it provides more relevant information to the user and helps them find everything they need in one place.

Therefore, when creating your content, you should explore the related subtopics. This is so you can include all the information that may help the user better understand the topic.

By mentioning related topics and subtopics, you also make it easier for search engines to understand what the content is about.

That’s because the search algorithm relies on the Knowledge Graph – a database of entities with basic information about them and how they are related to each other.

For example, if you talk about Waterloo and mention trains and travel, the algorithm will understand that you are talking about Waterloo Station and not the Battle of Waterloo.

Recency

More often than not, the freshness of content is related to its accuracy and credibility.

That’s why, when showing search results, Google strives to provide the newest relevant pages.

This means that even if you publish evergreen content, you should occasionally revisit and update it with more recent information.

Richness

Pages that feature diverse content including text, graphics, images, tables, videos, audio, etc. are more engaging to users, and, as a result, contribute to better SEO.

However, make sure not to overburden the page. This can affect its loading speed. All the multimedia content you add should be there because it adds value and may be useful to the visitor.

Call to Action

Call-to-action buttons may seem a little out of place in this list, but they are actually quite relevant.

They invite (or push) the user to take the next steps on their journey on your website, and, therefore, result in users clicking on more of your links, and spending more time on your website.

The more engaged the user is, the better impression this leaves the bots.

Mobile-Friendliness

We already mentioned mobile-friendliness when we talked about technical SEO. However, optimizing your page layouts and making your content more mobile-friendly are not entirely the same thing.

All in all, to be eye-pleasing and easy to read on a small screen, your content should have enough white space, short sentences and paragraphs, a lot of subheadings and bullets, and simple enough vocabulary.

4. Off-Page SEO: Proves Your Authority

Off-page SEO extends your credibility beyond your own website. Instead of “collecting backlinks,” the modern goal is to build signals of influence that prove your authority in a specific field. This includes high-value backlinks, brand citations, digital PR, industry collaborations, and professional reputation signals tied to authors and companies.

The most authoritative links now come from reputable publications, expert interviews, research contributions, industry events, or partnerships. A strong off-page strategy positions a brand as a recognized contributor to industry knowledge rather than a passive content publisher.

E-A-T plays a major role here as well. Author biographies, credentials, and verified case studies serve as external validation. Testimonials with measurable outcomes, portfolio results, research findings, and expert appearances (such as webinars or podcasts) reinforce the credibility of both the individual contributors and the organization. Search engines evaluate brands the same way humans do: they trust businesses with proven results and visible industry participation.

Off-page SEO is therefore about reputation. Companies that consistently demonstrate value beyond their own platform naturally strengthen their position as trusted industry leaders.

Backlinks

Backlinks are crucial for SEO, in fact, they are often quoted as the most important factor that determines your success in the SERPs.

The reason for this is that these are links from other websites toward yours and Google views them as the highest form of recommendation.

Why? They signify that a third party considers your content to be so valuable that it wants its readers to see it.

The more backlinks a page has, the higher its authority becomes.

However, although quantity never hurts, the quality and relevance of these links are what really matters.

Furthermore, links from websites with high authority are far more valuable than those from unpopular or low-quality domains. High-authority links transfer what is known as link equity (or the more colloquial “link juice”) and can boost the authority of your own pages.

This means that when building backlinks, you should always focus on those that will contribute to your page’s presence. Avoid opportunities that just waste time and resources on every link you can get your hands on.

Reputation Management

Online reputation is crucial for SEO. What people say about you can be the difference between making and breaking it.

Reviews on third-party websites and platforms are the backbone of your digital reputation. Although you can’t control what people say about you, you should always strive to answer all reviews – good and bad.

By engaging with people who left a negative opinion about your business, you can try to make amends and fix their impression of you. As a result, they could change their minds. Even if they don’t, it shows good manners. It can also affect the way other people see you – as someone who cares about the quality of their services.

Also, monitor mentions of your brands, and try to stay ahead of negative backlash. Keep track of what people say about you by using Google Alerts, as well as social listening tools.

Local Search

If you are a local business and your audience is concentrated in a limited area, optimizing your Google My Business profile can greatly contribute to your overall SEO.

There you can not only feature a link to your website, your address, and a map with your physical location, but you can provide images, answer questions, and add relevant information.

As mentioned, reviews are also an important feature.

In addition, you should strive to get featured in local directories. The backlinks from these are not very valuable. However, your presence in these listings can boost your reputation and credibility, bringing in significant traffic.

Social Media

Building profiles on all social media networks can affect your credibility. Even if you are not active on one of the popular platforms, do your best. Create a profile there and leave a message to potential customers. This way they can find you on other channels where you are more active.

Why do this? Search engines take profiles on third-party platforms as proof of your existence and credibility. Together with your brick-and-mortar address, phone number, email address, and other personal information, social media platforms confirm that you are a real entity.

Bottom Line

The 4 pillars of SEO define a framework that allows businesses to address search engine optimization strategically and make the most of it.

Each pillar consists of a group of factors. If implemented properly, they strengthen the whole structure and increase the website’s chance of success.

When optimizing your content, keep in mind that the ultimate purpose of SEO is to ensure that search engines understand what your pages are about, and are able to assess their quality. This way, they will show them to the right kind of users who are more likely to enjoy your content.

As a result, you will benefit from organic traffic and your business will thrive online.