The title tag of a web page has a lot of leverage for SEO. All search engines, especially Google, place a lot of weight on keywords in the tittle tag. So, that means you should cram as many keywords as possible in the title, right? The answer is no — you need to limit the length of the title tag.
First a little background. The title tag for a web page specifies a short phrase that is to be used as the title for that page. This is specified using the <title> HTML tag. For example:
<title>This is the title of this page</title>
The title tag does not appear in the actual body of the web page. Most all browsers show the title in the window bar, which is the bar across the top of the window on your screen. The title tag is also shown in most search engine results, such as in the following Google result:
The title tag is very important for SEO. Since the length of the title tag is limited and it represents the content of the page, search engines place a lot of importance on this tag. Notice that words used in a search are shown in bold in the search results, helping your entry to stand out and get more clicks from users. Also, only the first 66 characters or so of the title is displayed in Google search results (Yahoo shows more — about 100), and depending on the size of the window displaying your page, the title may be truncated in the browser title bar. This is one reason you want to keep your title length limited.
The first few words of the title get the most “weight” for SEO rankings, and the more words included in the title, the less weight is given to other words (so adding too many words to a title dilutes the benefit). Thus if you want to emphasize a keyword or phrase for a page, put it first in the title tag, and limit the overall length of the title.
So how long should a title tag be, and how do you decide what to include? Here are some guidelines:
1) It is best to limit the title to 66 characters, or about 8 words. It is OK to make it longer (up to about 100 characters, or 12 words), but you will get some dilution and not all of the tag will show in search results.
2) Make the title tag on each page unique, and use keywords specific to that page. Make sure any words used in the title tag are also in the the page body.
3) Put your most important words first in the title. Don’t repeat any given word more than once (repeating too often could be tagged as spam).
4) Phrase your tag as a title if you can, not just a list of keywords. It is OK to list several short phrases and use commas, vertical bars or dashes as separators. Use proper case (where each word is capitalized). Use phrasing that is attractive to users, since the title tag is shown in search results.
5) If you want to include your brand name or domain in your title, it is usually best (from an SEO perspective) to put it last, since you probably want to emphasize other keywords by putting them first. You will usually rank well for your brand or domain anyway.
6) Avoid using special characters in the title tag if you can, since not all search engines will display them correctly. In general, ©, ® and ™ (for copyright, registered trademark and trademark symbols) will work OK, but many other symbols and special ascii characters will show funny in the results, so avoid using them.
The bottom line is to keep your title tag short (8-12 words), focus on the important keywords for the page, and make it unique for each page on your website.