Better SEO performance by updating deprecated HTML tags

In today’s rapidly evolving digital landscape, HTML Development practices continue to evolve. Many HTML tags that were once staples in web design are now considered deprecated or obsolete. This comprehensive tutorial explains why these old HTML tags—such as <marquee>, <font>, <center>, <frame>, and others—are no longer recommended, and it provides step-by-step guidance on how to replace them with modern, SEO-friendly alternatives. Whether you’re a beginner or an experienced developer, this guide will help you update your code to meet current web standards and boost your site’s compatibility and SEO performance.

Introduction to Deprecated HTML Tags

Deprecated HTML tags are elements that were once part of early HTML standards but have been phased out in favor of more semantic, accessible, and maintainable alternatives. For many years, developers used tags like <marquee> for scrolling text, <font> for styling text, and <center> for aligning content. Although these tags still render in some browsers, they have been officially deprecated because they mix content with presentation, do not follow the principles of semantic HTML, and can negatively affect accessibility and search engine optimization (SEO).

By understanding why these tags were deprecated and learning how to implement modern HTML practices, you can significantly improve your website’s compatibility across browsers and devices while also enhancing your SEO performance.

Why Were These HTML Tags Deprecated?

The main reasons behind the deprecation of many HTML tags include:

Separation of Concerns: Early HTML tags often combined content structure with presentation. Modern web development emphasizes separating content (HTML) from presentation (CSS) and behavior (JavaScript).
Accessibility and Semantics: Modern HTML aims to use semantic tags that clearly describe the content. This not only improves accessibility for users with disabilities but also helps search engines understand and rank your content.
Responsive Design: Deprecated tags often hinder responsive design. Modern CSS frameworks and HTML5 elements facilitate fluid layouts that work across different devices.
Browser Consistency: Modern tags and attributes are standardized across browsers, which results in more consistent rendering and fewer cross-browser issues.
SEO Benefits: Clean, semantic code that adheres to modern web standards is easier for search engines to crawl, which can lead to better indexing and ranking.

Understanding these reasons is crucial, as they form the foundation for why modern HTML development practices are recommended. By replacing deprecated tags with updated alternatives, you not only follow best practices but also enhance your website’s overall performance and SEO.

Step-by-Step Guide to Replacing Deprecated HTML Tags

The process of modernizing your HTML code involves identifying deprecated tags, understanding their intended purpose, and implementing the appropriate modern HTML or CSS solutions. Let’s dive into specific examples and learn how to transition from old to new.

1. Replacing <marquee>

The <marquee> tag was widely used to create scrolling text but is now considered non-standard. Instead, CSS animations or JavaScript libraries offer more flexible and accessible solutions.

Deprecated Code Example:

HTML

<marquee behavior="scroll" direction="left" scrollamount="5">
	This text scrolls across the screen.
</marquee>

Modern Replacement Using CSS Animation:

HTML

<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>CSS Animation Example</title>
	<style>
		.scrolling-text {
			width: 100%;
			white-space: nowrap;
			overflow: hidden;
			box-sizing: border-box;
		}
		.scrolling-text span {
			display: inline-block;
			padding-left: 100%;
			animation: scroll-left 10s linear infinite;
		}
		@keyframes scroll-left {
			from {
				transform: translateX(0);
			}
			to {
				transform: translateX(-100%);
			}
		}
	</style>
</head>
<body>
	<div class="scrolling-text">
		<span>This text scrolls across the screen using CSS animation.</span>
	</div>
</body>
</html>

This modern approach uses CSS keyframe animations to achieve the scrolling effect, offering better control, improved accessibility, and enhanced performance.

2. Replacing <font>

The <font> tag was historically used to change text color, size, and style. Today, CSS is the preferred method for styling text.

Deprecated Code Example:

HTML

<font color="red" size="4">This is a sample text.</font>

Modern Replacement Using CSS:

HTML

<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>CSS Styling Example</title>
	<style>
		.styled-text {
			color: red;
			font-size: 1.5em;
		}
	</style>
</head>
<body>
	<p class="styled-text">This is a sample text styled using CSS.</p>
</body>
</html>

Using CSS classes for styling separates the design from the content, ensuring a cleaner, more maintainable codebase that is easier for search engines to index.

3. Replacing <center>

The <center> tag was used for centering content, but modern CSS provides much more flexible alignment options.

Deprecated Code Example:

HTML

<center>
	<p>This paragraph is centered.</p>
</center>

Modern Replacement Using CSS:

HTML

<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>Centering Content Example</title>
	<style>
		.centered-content {
			text-align: center;
		}
	</style>
</head>
<body>
	<div class="centered-content">
		<p>This paragraph is centered using CSS.</p>
	</div>
</body>
</html>

The use of CSS for centering content provides more responsive and versatile layout options, which are essential for modern web design.

4. Replacing <frame> and <frameset>

Frames were once used to display multiple HTML documents within a single browser window. However, frames cause usability and SEO issues, and they have been replaced by more modern methods such as <iframe> for embedding content or CSS-based layouts for multi-column designs.

Deprecated Code Example:

HTML

<frameset cols="25%,75%">
	<frame src="navigation.html">
	<frame src="content.html">
</frameset>

Modern Replacement Using <iframe> and CSS Layouts:

For embedding external content, <iframe> is still valid:

HTML

<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>Embedding Content with iframe</title>
	<style>
		.layout {
			display: flex;
		}
		.navigation {
			width: 25%;
		}
		.content {
			width: 75%;
		}
	</style>
</head>
<body>
	<div class="layout">
		<div class="navigation">
			<!-- Navigation content here -->
			<iframe src="navigation.html" title="Navigation"></iframe>
		</div>
		<div class="content">
			<!-- Main content here -->
			<iframe src="content.html" title="Content"></iframe>
		</div>
	</div>
</body>
</html>

For layouts, modern CSS techniques (such as Flexbox or CSS Grid) allow you to design responsive multi-column layouts without the drawbacks of frames.

5. Replacing <big> and <small>

The <big> and <small> tags were used to change text size in a relative manner. However, these effects are better achieved with CSS for consistency and improved design flexibility.

Deprecated Code Example:

HTML

<p>This is a \<big\>big\</big\> text and this is a \<small\>small\</small\> text.</p>

Modern Replacement Using CSS:

HTML

<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>Relative Text Size Example</title>
	<style>
		.big-text {
			font-size: 1.25em;
		}
		.small-text {
			font-size: 0.85em;
		}
	</style>
</head>
<body>
	<p>This is <span class="big-text">big</span> text and this is <span class="small-text">small</span> text.</p>
</body>
</html>

CSS offers precise control over typography and ensures that your design remains consistent across different browsers and devices.

6. Replacing <applet>

The <applet> tag was used to embed Java applets in a web page. With the decline of Java applets and the advancement of web technologies, alternatives such as JavaScript libraries and HTML5’s <canvas> or <video> tags provide more secure and compatible solutions.

Deprecated Code Example:

HTML

<applet code="MyApplet.class" width="300" height="300"></applet>

Modern Replacement Using HTML5 and JavaScript:

For interactive content, consider using a <canvas> element:

HTML

<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>HTML5 Canvas Example</title>
	<style>
		canvas {
			border: 1px solid #000;
		}
	</style>
</head>
<body>
	<canvas id="myCanvas" width="300" height="300"></canvas>
	<script>
		const canvas = document.getElementById('myCanvas');
		const ctx = canvas.getContext('2d');
		ctx.fillStyle = '#FF0000';
		ctx.fillRect(50, 50, 200, 200);
	</script>
</body>
</html>

This approach leverages HTML5 and JavaScript for dynamic and interactive graphics without the security and compatibility issues associated with Java applets.

7. Replacing <dir>, <menu>, and <isindex>

The <dir> tag, along with <menu> and <isindex>, have fallen out of favor due to their limited semantic meaning and inconsistent behavior across browsers. Modern HTML provides better structures like <ul>, <ol>, and <nav> for creating navigation menus and lists.

Deprecated Code Example:

HTML

<dir>
	<li>Item 1</li>
	<li>Item 2</li>
</dir>

Modern Replacement Using <ul> and <nav>:

HTML

<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>Navigation Menu Example</title>
	<style>
		nav ul {
			list-style-type: none;
			padding: 0;
		}
		nav li {
			display: inline;
			margin-right: 15px;
		}
	</style>
</head>
<body>
	<nav>
		<ul>
			<li><a href="#item1">Item 1</a></li>
			<li><a href="#item2">Item 2</a></li>
		</ul>
	</nav>
</body>
</html>

Replacing deprecated tags with semantic HTML elements like

not only improves accessibility but also helps search engines better understand the structure of your website.

8. Replacing <strike>, <u>, <b>, <i>, and <tt>

Tags such as <strike>, <u>, <b>, <i>, and <tt> were traditionally used for text decoration. Modern practices encourage the use of CSS for styling and semantic HTML elements to convey meaning. For example, use <del> for deletions, <ins> for insertions, <strong> for important text, and <em> for emphasized text.

Deprecated Code Example:

HTML

<p>This is <strike>strikethrough</strike> and this is <u>underlined</u> text.</p>
<p>This is <b>bold</b> and this is <i>italic</i> text.</p>

Modern Replacement Using Semantic HTML and CSS:

HTML

<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>Semantic Text Styling Example</title>
	<style>
		.underlined {
			text-decoration: underline;
		}
	</style>
</head>
<body>
	<p>This is <del>strikethrough</del> and this is <span class="underlined">underlined</span> text.</p>
	<p>This is <strong>bold</strong> and this is <em>italic</em> text.</p>
</body>
</html>

Using semantic tags like <strong> and <em> communicates meaning to search engines and assistive technologies, while CSS handles the presentation.

9. Replacing <xmp>, <plaintext>, and <listing>

The <xmp>, <plaintext>, and <listing> tags were used to display preformatted text or code examples in a very raw format. However, these tags can conflict with modern document parsing and are replaced by the <pre> element, often enhanced with syntax highlighting libraries for code display.

Deprecated Code Example:

HTML

<xmp>
	<html>
		<head>
			<title>Deprecated Code</title>
		</head>
		<body>
			This is a sample code.
		</body>
	</html>
</xmp>

Modern Replacement Using <pre>:

<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>Preformatted Code Example</title>
	<style>
		pre {
			background-color: #f4f4f4;
			padding: 10px;
			overflow-x: auto;
		}
	</style>
</head>
<body>
	<pre>
		&lt;html&gt;
			&lt;head&gt;
				&lt;title&gt;Modern Code&lt;/title&gt;
			&lt;/head&gt;
			&lt;body&gt;
				This is a sample code.
			&lt;/body&gt;
		&lt;/html&gt;
	</pre>
</body>
</html>

The <pre> tag preserves whitespace and formatting, making it ideal for displaying code while remaining compliant with HTML5 standards.

SEO Benefits of Modern HTML Practices

Modernizing your HTML by replacing deprecated tags with semantic and accessible alternatives brings numerous SEO benefits:

Improved Crawlability: Search engine bots can better understand your site structure, which can lead to improved indexing.
Enhanced Accessibility: Semantic HTML elements enhance accessibility, indirectly boosting your site’s SEO by increasing user engagement.
Faster Load Times: Modern CSS and JavaScript techniques are generally more efficient than older methods, leading to faster page load times—a key ranking factor.
Responsive Design: Modern layouts built with Flexbox or Grid adapt better to various devices, ensuring a positive user experience across desktops, tablets, and mobile devices.
Cleaner Code: Cleaner, maintainable code reduces errors and increases compatibility with future web standards, helping your site remain relevant in an ever-changing digital environment.

Best Practices for Modern HTML Development

As you transition from deprecated tags to modern HTML, keep these best practices in mind:

Separation of Content and Presentation: Use HTML for structure and CSS for presentation. This separation makes your code more modular and easier to update.
Embrace Semantic HTML: Use tags like <header>, <nav>, <main>, <article>, <section>, and <footer> to define the different parts of your webpage clearly.
Responsive Design: Leverage CSS media queries, Flexbox, and CSS Grid to create layouts that adapt to various screen sizes.
Accessibility: Ensure that your website is accessible by using proper ARIA roles, semantic tags, and descriptive alt attributes for images.
Regular Updates: Keep up with modern web standards and update your code accordingly to avoid legacy practices that can negatively impact SEO and user experience.

Conclusion

Modern HTML development is about creating websites that are fast, accessible, and SEO-friendly. Replacing deprecated HTML tags such as <marquee>, <font>, <center>, <frame>, <applet>, and others with modern alternatives is a critical step toward achieving this goal. By adopting CSS for styling, utilizing semantic HTML elements, and following best practices, you ensure that your website not only complies with modern standards but also provides an optimal user experience across all devices.

Now that you have a clear understanding of why and how to replace deprecated HTML tags, it’s time to apply these best practices to your own projects. Modern HTML development is a continuous process of learning and adapting, so stay updated with the latest trends and standards to keep your websites at the forefront of web design and SEO performance.

Happy coding, and enjoy the journey towards creating a more modern, accessible, and SEO-friendly web!