Summary: Google recognises a number of meta tags that allow you to provide it with information about your website.
What are meta tags? Meta tags are a means for you to let Google (and other search engines) know certain bits of information about your website. The tags appear in the head section of your page. So the head of the page will look something like this:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>Great page about SEO and SEO techniques</title> <meta name="description" content="Unique page description goes here" /> <meta name="keywords" content="Add a few keywords" /> </head>
Google understands only certain meta tags. That doesn’t mean you can’t use any others – it just means Google will ignore them.
Description tag
Example:
<meta name="description" content="White hat SEO techniques versus black hat SEO techniques - which are more effective" />
The description tag offers a short description of the page – it’s not visible on the page but Google and the other engines may use it in the search results (sometimes they use a snippet from the page instead if they think it’s more relevant, or the Open Directory listing if you have one). Most SEO experts recommend that your description tag is no longer than 160 characters. Here, we like to limit that to 120 characters for our really important pages as this is what Google seems to like best.
Keywords
Example:
<meta name="keywords" content="seo, search engine optimisation" />
We’re including this meta tag because just about every website owner will use it, but you should know that Google has quite categorically stated:
“Google doesn’t use the “keywords” meta tag in our web search ranking”.
So what you put in there will not influence your ranking in Google. Will it influence your ranking elsewhere? Doubtful – there might be a small number of less credible search engines that still look at this tag and for that reason, you might as well insert some keywords in there .. but don’t hold your breath for anything great to happen as a result!
Page title
Example:
<title>Great page about SEO and SEO techniques</title>
Technically the title tag isn’t a meta tag at all. It’s used by most search engines including Google to display a title in the search results for the page. The title tag also appears at the top of the page in the user’s browser. Most SEO experts agree that the title shouldn’t be longer than 60 characters, and you should put your key words early on in the title (which should be relevant to the content of the page).
Meta tags for search engines
Example:
<meta name="robots" content="..., ..." /> <meta name="googlebot" content="..., ..." />
There are a bunch of meta tags that control how search engine bots like Googlebot crawl and index your site. If you want to send an instruction to all search engine bots, you can identify this by using ‘robots’ as above – if you’re sending an instruction just to Googlebot, you can identify this as Googlebot, as per the example above.
You can use the following values and when you’re using multiple values, you separate them with a comma like this:
<meta name="googlebot" content="noindex, nofollow" />
noindex
Example:
<meta name="robots" content="noindex" /> <meta name="googlebot" content="noindex" />
The top example means you’re specifying no search engine can index your page – the bottom example means Google is not allowed to index your page – all other search engines can. In practice, search engine bots don’t stick very well to this – so if you really, really don’t want them indexing some content it’s better to block them from doing that in your .htaccess file.
nofollow
Example:
<meta name="robots" content="nofollow" /> <meta name="googlebot" content="nofollow" />
‘No follow’ prevents Googlebot from following links from the page. Well… saying that, Google say that ‘in general’ they don’t follow them and as a result, page rank / anchor text is not transferred. This means the link is less valuable to the target site for SEO.
nosnippet
Example:
<meta name="robots" content="nosnippet" /> <meta name="googlebot" content="nosnippet" />
Sometimes Google displays a snippet from your page that usually highlights the user’s search terms on the page. You might not want them to do that because you want them to show your description meta tag instead. The ‘nosnippet’ meta tag prevents a snippet from being shown in the search results. Be careful about using this though – Google say (in their blog):
“We know from user studies that users are more likely to visit your site if the search results show the snippet. Why? Because snippets make it much easier for users to see why the result is relevant to their query. If a user isn’t able to make this determination quickly, he or she usually moves on to the next search result.”
noodp
Example:
<meta name="robots" content="noodp" /> <meta name="googlebot" content="noodp" />
‘ODP’ in ‘noodp’ above stands for ‘Open Directory Project’. This meta tag prevents Google from showing the alternative description from any ODP/DMOZ listing that you have, instead of your carefully crafted description. Of course, you could use this and Google might still decide to show an extract (snippet) from your page instead, that can’t be helped – the key is just to make your description as relevant as possible and hope that Google uses it.
noarchive
Example:
<meta name="robots" content="noarchive" /> <meta name="googlebot" content="noarchive" />
The noarchive meta tag prevents Google from showing the cached link for a page in its search results. This can be quite handy if you’ve made some changes that potentially might not show up to the user because a cached version is displayed – a change to images without renaming them, for example.
unavailable_after:[date]
Example:
<meta name="googlebot" content="unavailable_after: 25-Aug-2007 15:00:00 EST">
This meta tag lets you specify the exact time and date you want to stop crawling and indexing of this page. You use this for pages where you know they are going to expire (an example might be a page telling your users about a forthcoming change – once the change is live, the page is no longer needed).
noimageindex
Example:
<meta name="googlebot" content="noimageindex">
The noimageindex meta tag lets you specify that you do not want your page to appear as the referring page for an image that appears in Google search results. However, it’s possible Google will still index the images as they state on their Webmaster Guidelines. If you want to stop them indexing the images altogether, add an entry in your htaccess file. To block all search engines, add:
User-agent: * Disallow: /images/
Or, just to block Google, add:
User-agent: * Disallow: /images/
X-Robots-Tag
You can also specify the above set of metatags in the header of your pages using the ‘X-Robots’Tag’ HTTP header directive. This enables you to find tune crawling and indexing of non-HTML files such as graphics, PDFs and other types of documents. I think this deserves its own post so I’ll work on creating one that explains what you can do with that.
Translation
Example:
<meta name="google" content="notranslate" />
When Google detects that your page is in a different language, it translates your page and provides a link to the translation. Google translations are not perfect and you might want to provide your own translation. Using this meta tag, you can block Google from displaying the translation link.
Site verification
Example:
<meta name="google-site-verification" content="..." />
This meta tag when used on the top level page of your site, verifies ownership of the site for the purpose of Webmaster Tools. We really recommend using Webmaster Tools as they provide all sorts of really useful information on how your site is performing. You can also verify ownership by uploading a html file that you’ll find within Webmaster Tools, if you prefer.
Content/character set
Example:
<meta http-equiv="Content-Type" content="...; charset=..." />
This meta tag defines the page’s content type and character set. Many new web developers overlook how important this tag is. It’s important to label web documents properly – it tells the browser how to display the document. If you don’t label them properly, the browser will just use the visitor’s preferred or default encoding and this can result in the page displaying incorrectly.
Here are some examples:
XML including XHTML:
<?xml version="1.0" encoding="utf-8" ?>
HTML and XHTML served as HTML, always place the meta tag inside the head:
<meta http-equiv="Content-Type" content="text/html;charset=utf-8" >
Don’t forget to add a slash at the end for XHTML:
<meta http-equiv="Content-Type" content="text/html;charset=utf-8" />
Refresh
Example:
<meta http-equiv="refresh" content="...;url=..." />
The refresh meta tag sends the visitor to a new URL after a period of time. Most often it’s used as a way to redirect visitors but it’s not supported by all of the browsers and can cause confusion to the visitor. It’s not recommended by W3C – and we’d suggest using a 301 in your .htaccess file instead.
Example:
redirect 301 /index.html http://www.yourdomain.com/index.html
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1 Response to “Which meta tags does Google recognise?”
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Make sure you enter the * required information where indicated. Responses are moderated so please no link dropping, no keywords or domains as names; do not spam, and do not advertise!
said at 8:46 pm on November 8th, 2010
Great article!! It really helped me understand all the meta tags…
Thanks buddy! Keep it up!