HTML Deprecated Tags
In this page:
Why These Tags Were Deprecated
Early HTML mixed content structure and visual presentation together in the same tags, meaning a page's styling was baked directly into its markup. As CSS matured into a complete, dedicated styling language, HTML deprecated most presentational tags in favor of keeping structure (HTML) and style (CSS) cleanly separated -- a principle that makes sites easier to maintain and restyle.
Note: If you inherit an old codebase full of deprecated tags, treat it as a strong signal to gradually migrate that styling into CSS rather than extending it further.
Warning: A tag still rendering in your browser today does not mean it is safe to use going forward -- browsers keep old tags working purely for backward compatibility with decades-old websites.
Example: Why These Tags Were Deprecated
<!-- Old: presentation mixed into markup -->
<font color="red">Warning text</font>
<!-- Modern: structure and style separated -->
<p style="color: red;">Warning text</p>Text Styling Tags to Replace
<font>, <basefont>, <big>, <tt>, and <strike> all controlled font family, size, color, or basic text effects directly in markup. Each has a direct CSS replacement: font-family/color/font-size for <font> and <basefont>, font-size for <big>, font-family: monospace for <tt>, and text-decoration: line-through (or the semantic <s> element) for <strike>.
Note: When migrating old markup, replace <font color="..." size="...">text</font> with a styled <span> or a CSS class -- never leave the old tag in place.
Warning: <strike> is easy to confuse with the still-valid <s> element -- <strike> is deprecated, while <s> (a different, still-supported tag) is the modern equivalent.
Example: Text Styling Tags to Replace
<!-- Deprecated -->
<font size="5" color="blue">Big blue text</font>
<strike>Old price</strike>
<!-- Replacement -->
<span style="font-size: 20px; color: blue;">Big blue text</span>
<s>Old price</s>Layout Tags to Replace
<center> and <marquee>-era layout tags forced specific visual positioning directly into markup. <center> is replaced by text-align: center (for text) or margin: 0 auto (for centering a block element), while table-based layouts using deprecated attributes are replaced entirely by CSS Flexbox or Grid.
Note: Replace any <center> tag with text-align: center in CSS, or margin: auto plus a defined width if you are centering a block-level container.
Warning: Old table-based page layouts (using tables purely for visual positioning rather than tabular data) are considered an outdated practice, even though the <table> tag itself remains fully valid for actual data.
Example: Layout Tags to Replace
<!-- Deprecated -->
<center>Centered text</center>
<!-- Replacement -->
<p style="text-align: center;">Centered text</p>Frame and Embed Tags to Replace
<frame>, <frameset>, and <noframes> split a browser window into multiple independently-scrolling documents, a technique now replaced by <iframe> (for embedding one external document) or CSS Grid/Flexbox layouts (for splitting a single page into visual regions). <applet> (Java applets) is replaced by <embed> or <object> for any remaining plugin content, though modern web apps avoid browser plugins entirely.
Note: If you see a <frameset>-based layout, it needs a full redesign using <iframe> or a CSS-based multi-panel layout -- there is no simple drop-in replacement.
Warning: <applet> relied on the Java plugin, which no modern browser supports at all anymore, making any surviving applet-based content completely non-functional today.
Example: Frame and Embed Tags to Replace
<!-- Deprecated -->
<frameset>
<frame src="page1.html">
</frameset>
<!-- Replacement -->
<iframe src="page1.html"></iframe>Quick Reference: Deprecated Tag to Modern Replacement
As a fast lookup: <acronym> to <abbr>, <applet> to <embed>/<object>, <basefont>/<font> to CSS font properties, <big>/<small> visual sizing to CSS font-size, <center> to CSS text-align/margin, <dir> to <ul>, <frame>/<frameset>/<noframes> to <iframe> or CSS layout, <strike> to <s> or <del>, and <tt> to <code> or CSS font-family: monospace.
Note: Keep this mapping handy when auditing an old codebase -- most deprecated-tag migrations are a direct one-to-one swap to a CSS property or a still-valid semantic tag.
Warning: A handful of these deprecated tags (like frameset) require a structural redesign rather than a simple one-to-one swap, since their entire layout model has been replaced.
Example: Quick Reference: Deprecated Tag to Modern Replacement
<!-- <acronym> -> <abbr> -->
<abbr title="HyperText Markup Language">HTML</abbr>
<!-- <tt> -> <code> -->
<code>console.log()</code>- Copy-pasting old code containing <center>, <font>, or <marquee>-style tags into a new project without realizing they were deprecated years ago.
- Assuming a deprecated tag "still works fine" is the same as it being valid -- most still render in browsers today purely for backward compatibility with old websites, not because they are recommended.
- Not knowing the CSS replacement for a deprecated tag, and reaching for inline styles as a workaround instead of the clean, intended CSS property.
- Deprecated tags mixed visual styling into HTML markup; CSS now handles all of that styling instead.
- Browsers still render most deprecated tags for backward compatibility, but they are excluded from the HTML5 specification and should not be used in new code.
- Every deprecated presentational tag has a direct CSS equivalent that offers more control and keeps styling separated from structure.
All tags on this page still render in current browsers for backward-compatibility reasons, but none are part of the HTML5 specification and none should be used in new projects.
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