What are the most important meta tags? An overview

Meta tags are coded information stored in the head section of an HTML document and serve to provide metadata. They do not appear on the actual webpage but are read by user agents like browsers.

What are HTML meta tags?

HTML meta tags are HTML elements designed to provide additional information about a webpage to facilitate the analysis of the HTML file and the management of its content. HTML meta tags generally follow a similar structure: first, an element is defined, then content is assigned to it. This results in the following schema for meta information:

<meta name="Element Name" content="assigned content"/>

While metadata used to play a crucial role in search engine optimization for HTML pages, their influence on the ranking of Google, Bing, and others is now considered rather low. However, it is still advisable for website operators to maintain the information in the HTML head and provide detailed meta information. This is because metasearch engines and local search scripts still find them relevant. Additionally, meta tags offer the opportunity to define instructions for controlling search robots (web crawlers).

Important meta tags

The list of possible elements in the HTML head is long. Besides essential details like the page title, the page description, and the definition of the character set used, the header (the title section of HTML files) offers the possibility to provide extensive information for user agents. This allows website operators to define relevant keywords or specify a page theme via meta tags. Additionally, authors or publishers can be named, or copyright information can be included in the meta tags.

However, not all of this information is relevant for interaction with web browsers and search robots. It’s different with meta tags that control the behavior of user agents by prohibiting the indexing of the respective HTML page or preventing the web crawler from following outgoing links. The following table provides an overview of the most important meta elements:

Title

Strictly speaking, the title is not a meta-element but an independent HTML tag. Due to its significance for interaction with user agents, it’s often mentioned in connection with meta information. As a required element in the HTML head, the title is usually placed before all other meta-tags. Read by web browsers, it appears in the title bar of a tab or window, as the default name when setting bookmarks, and in the web browser’s history. Additionally, all major search engines use the <title> tag as the heading for entries in the search results lists (SERPs). It thus has a significant influence on the click behavior of internet users during web searching.

A suitable title is essential for a good CTR. As part of on-page optimization, it should be ensured that the title does not exceed the search engine display length of a maximum of 580 pixels—this is about 50 to 60 characters. It is also recommended to place the main keyword of a webpage in the <title> tag. For example, the following information is stored as the title of this webpage:

<title>Overview of HTML Meta Tags - IONOS</title>

Character encoding

If the character set has not already been defined in the HTTP header, you should include this information via HTML. This prevents, for example, incorrect display of special characters in other languages i.e. German umlauts. To specify the character set or encoding, use the following meta tag:

<meta charset="UTF-8"/>

This meta information becomes relevant when a browser does not receive HTML files via HTTP, but retrieves them directly from the hard drive.

Description

The description (also called meta description) provides space for a brief description of the website’s content. Since this meta tag is often adopted as a snippet in the SERPs by established search engines like Google, Bing, and others, careful editorial preparation is recommended. Due to its importance for click behavior in web search, the description is considered one of the most important SEO meta tags.

Website operators should ensure that the description text does not exceed 920 pixels (about 150 to 160 characters). Otherwise, there’s a risk that the excess characters will be cut off in the search engine listing. The meta description should provide a concise and attractive summary of the page content.

These meta tags you should know! HTML meta tags encode information for browsers and search engines. But which details are truly important?

Author and Copyright

The meta tags author and copyright give website operators the opportunity to include in the source code of an HTML page who built the corresponding website and who holds the copyright for the page content. In some content management systems (CMS), the author tag is sometimes assigned automatically.

<meta name="author" content="Author Name" />
<meta name="copyright" content="Copyright Holder" />

Instructions for web crawlers (bots)

One of the main functions of meta tags is to convey index instructions to search engine crawlers. These are defined at page level by robots metadata. The following meta tags are used to determine whether a page is added to a search engine index and if it is available for a web search. They can also specify whether outgoing page links should be followed or ignored by the crawler. In this way, meta robot data proves itself to be one of the most relevant kinds of SEO meta tags.

index

To allow the search engine to index an HTML page, use the following meta tag:

<meta name="robots" content="index"/>

As the indexing of websites is the standard behavior of web crawlers (search robots), this information is generally unnecessary.

noindex

• No comments needed.

If an HTML page should not be included in the search engine index, you must explicitly define this:

<meta name="robots" content="noindex"/>

The name attribute robots targets all search engine crawlers. The content attribute noindex contains the information that indexing is prohibited. If you want to prevent indexing for specific robots only, you can do so by choosing an alternative name attribute like googlebot.

follow

The standard behavior of a web crawler includes following the outgoing links of an HTML page. If this is desired, it can be expressed through the following meta-robot specification:

<meta name="robots" content="follow"/>

Even this meta tag is essentially redundant because the crawlers of all major search engines typically follow hyperlinks automatically unless otherwise specified.

nofollow

If you want to prevent a search robot from reaching subordinate pages of a web presence via hyperlinks or from following references to other domains, you can achieve this with the following meta tag:

<meta name="robots" content="nofollow"/>

This asks the crawler not to pass PageRank through outgoing links. Until 2019, Google strictly followed this instruction; since then, it is considered a suggestion—Google may still follow the links.

The meta tags index/noindex and follow/nofollow can be used individually or in combination. For example, it can be specified that a page may be included in the index, but the hyperlinks should be ignored by the crawler. Alternatively, both actions by the search robot can be prohibited or allowed.

<meta name="robots" content="index,nofollow" />
<meta name="robots" content="index,follow" />
<meta name="robots" content="noindex,nofollow" />

HTTP equivalents

Using the http-equiv attribute, meta elements can contain equivalents to information in the HTTP header. This information is read, for instance, as a substitute if the web server hasn’t been configured accordingly. The rule is that a same-named HTTP header is preferred over HTML meta tags.

cache-control

To ensure fast Internet operation, it is common for websites to be cached on proxy servers or in the browser cache so that they can be loaded faster on subsequent calls. This process can be prevented with the meta tag cache-control with the value no-cache:

<meta http-equiv="cache-control" content="no-cache"/>

Web pages tagged with this meta tag must be reloaded from the web server every time the page is accessed. This slows down page loading, but it can be useful—such as when a website offers continuously changing content.

expires

Instead of completely preventing caching, you can use the http-equiv attribute to define an expiration date for the retrieved HTML data. The following meta tag is used for this purpose:

<meta http-equiv="expires" content="Expiration time in seconds"/>

HTML pages can be assigned any expiration date using meta tags. Once the defined time span has elapsed, a web browser is prompted to load the corresponding HTML documents from the original address. If content must always be loaded from the original page, an expiration time of 0 seconds is chosen. For a 12-hour expiration time, website operators choose 43,200 seconds.

<meta http-equiv="expires" content="0"/>
<meta http-equiv="expires" content="43200"/>

Alternatively, any time periods, as well as exact dates and times, can be defined. These must be specified in the international format and according to Greenwich Mean Time (GMT).

<meta http-equiv="expires" content="Sat, 07 Feb 2016 00:00:00 GMT"/>

refresh

Meta tags with the http-equiv attribute offer a way to set up a simple form of redirection. Similar to the expires tag, the refresh tag defines an expiration time. Once reached, user agents like web browsers or search engine crawlers are redirected to a predetermined URL. In the example code, the redirection takes 10 seconds to the IONOS homepage.

<meta http-equiv="refresh" content="10; url=https://www.ionos.com/"/>

Since the refresh tag is not supported by every web browser, the committee for standardizing techniques on the World Wide Web (World Wide Web Consortium, W3C) recommends a server-side implementation using the HTML status code 301 instead of redirection via meta tags (as noted in our article “The Most Important HTTP Status Codes at a Glance”).

Examples of meta tags in code

Below you will find a code example that represents a simple but complete head section of a webpage in HTML. It contains the most relevant meta tags that we have introduced to you in this article:

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<!-- Meta-Tag for the page title -->
<title>Overview of HTML meta tags - IONOS</title>
<!-- Meta-Description  -->
<meta name="description" content="You should know these meta-tags! HTML meta-tags code information for browsers and search engines. But which details are really important?">
<!-- Robots Meta-Tag -->
<meta name="robots" content="index, follow">
<!-- Meta-Tag for the author of the page -->
<meta name="author" content="John Smith">
<!-- Meta-Tag for copyright -->
<meta name="copyright" content="John Smith 2025">
<!-- Meta-Tag for the cache expiration time (optional) -->
<meta http-equiv="expires" content="Sat, 01 Jan 2025 00:00:00 GMT">
<!-- Meta-Tag to prevent caching -->
<meta http-equiv="cache-control" content="no-cache">
</head>
<body>
<h1>Welcome to Our SEO Tips for 2025</h1>
<!-- Content of the page -->
</body>
</html>