How to use HTML, CSS and Javascript to improve your SEO

Until a few years ago, it was common knowledge that Google couldn’t even read CSS markup.

If you read SEO tutorials from more than a few years ago, you might find steps on how to block Google from your CSS or JavaScript.

But today not only do we have confirmation that Google can read it, but they will warn you if you block them for it.

The message reads: Disallowing the crawling of Javascript or CSS files in your site’s robots.txt directly affects how well our algorithms render and index your content and may result in suboptimal rankings.

As a local SEO company, you don’t have to be an HTML and CSS expert with complicated knowledge of all HTML parameters.

You are expected to know how to read HTML and CSS, make changes to code, and modify existing blocks of code.

Knowledge of HTML, CSS and JavaScript, taken together, will enable you to understand how to implement structured data and optimize your content for search.

What is HTML

HTML, or Hyperext Markup Language, can be thought of as the skeleton of a website.

It’s the code that contains the content and meta information that search engines use to understand what a website is about.

A website written in pure HTML won’t look that great, but it will be lightning fast and likely optimized for organic search.

Using the correct HTML tags

When a search engine crawler comes across your text, it looks at the website’s HTML tags.

This knowledge lets search engines like Google decide what the content is about and how to categorize the data.

Let’s take a look at some of the most important HTML tags.

title tag

The title tag must approximate the title of the post.

Also, it’s best to keep it at 60-70 characters.

Longer, and it might be shortened in SERPs.

Introduce your brand name in the titles as well.

meta description tag

The meta description tag allows you to specify how you want to describe the content in search listings.

It will be within placed, and it’s better to use the keyword in the title as well as the meta description tag without overusing it in the content.

header tags

Header tags are used to break down content and encourage reading.

The header tags used are:

for website titles.

for the topic

for the points on the topic.

for the sub-items

can be used for bases of h4

alt tags

Search algorithms cannot decide which photos to select for transfer.

This is when the ALT comes into play.

Search engines don’t know what the image is without the ALT.

robot day

This is useful if you want to stop indexing certain posts.

Here we use: .

In this situation, Google neither indexes material nor follows any links and does not consider link juice when calculating rankings.

What is CSS?

CSS or Cascading Style Sheets is the interface of a website.

It allows granular control over style, fonts, and all visual aspects of a website.

Generally, global CSS is written to style elements like the header, footer, navigation, and occasionally even the main content itself.

Therefore, it’s a best practice to ensure that all shared CSS is kept in a style sheet.

If you need to design unique elements like a blog post, team page, or about us page, individual style sheets can be used in combination for each page.

Highlighting keywords via CSS

You may have come across webpages with seemingly random words highlighted in bold.

These sites try to improve their search rankings by helping search engines find their keywords.

You can use CSS to hide these tags from your readers.

This way you can keep your content reader-friendly and ensure that search engines find the most important words at the same time.

CSS for content organization

Search engines don’t scan your page visually, but based on the code.

As a result, your page may not be read as you would expect.

The search engine reads everything on a page from top left to bottom right.

Assuming you have a navigation or sidebar before the actual content, the search engine will read those sections first.

This will lower your ranking on the search results page because you will have duplicate content at the top of your page.

By using CSS you can organize your code however you want.

You can place your most valuable and keyword-rich content at the top and move less important sections below the main content.

Reducing the code-to-content ratio

Because using CSS makes your webpage lighter, it also reduces your code-to-content ratio.

Better indexing makes your content easier not only for users but also for web crawlers.

If your page is well organized and doesn’t contain a lot of extra HTML code, crawlers can quickly determine what your page is about.

This can improve your ranking in search engines.

What is JavaScript?

JavaScript serves a variety of purposes, including image galleries, dynamic layouts, games, and even unique responses to odd user behavior.

JavaScript and Google tend to play well together, but there are a lot more technical details about how JavaScript affects SEO that we won’t go into here.

The most important thing to remember is to avoid having your website load content via JavaScript.

If it’s important, make sure it’s in the skeleton of your site and not in the JavaScript code.

But first, let’s take a look at some of the common terms.


Crawling is the process by which Google discovers a page on your website.

Google uses web crawlers, often referred to as spiders, to discover web pages and regularly update their index.


Indexing refers to the process of analyzing the content and relevance of each crawled webpage and adding that page to Google’s index of webpages that may be included in search results.

Simply put, websites that are not indexed by Google will not appear in search results.


The ranking process begins when a user performs a search.

In order to provide the most useful and relevant search results, search engines need to do some math and pull the best possible results from their index of web pages.

It involves the following three critical steps.

  • Analysis of the intent and context of the search query
  • Identifying the web pages that are eligible to be displayed for the search result
  • Sorting the websites in question according to their importance and relevance to the search query

Build website structure

It is recommended to always use HTML to create the basic structure of a website.

You can always use JavaScript later to serve content or make the appearance more appealing once you’ve laid out the basic structure with HTML.

This ensures that Google can access the HTML code and users can benefit from JavaScript.

Typically, websites that use JavaScript are rendered on the client side (usually a web browser).

If you implement pre-rendering, you should follow Google’s quality guidelines and display the same content to all users.

Ideally, you should serve the same content to all user agents accessing your webpage.

Having different content for different user agents means cloaking, which is a bad practice that could carry severe penalties.

Final Thoughts

All in all, a basic understanding of how HTML, CSS and JavaScript work is a must for a professional SEO company.

Not only will this save your time when you encounter a glitch, but it will also enable you to improve a website’s traffic in the most efficient manner.

Written by Sheryl Jones

Sheryl is a Senior Marketing Specialist at Uplers and has a wealth of experience in creating well-defined user journeys across the digital marketing space. She uses her expertise in digital marketing to help companies achieve significant ROIs.

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