Google changes the titles of search results sometimes. This is nothing new, but the company is shedding a bit of light on the process, saying their alternative titles usually improve clickthrough rate.

Google Webmaster Trends Analyst Pierre Far writes on the Google Webmaster Central Blog, “Page titles are an important part of our search results: they’re the first line of each result and they’re the actual links our searchers click to reach websites. Our advice to webmasters has always been to write unique, descriptive page titles (and meta descriptions for the snippets) to describe to searchers what the page is about.”

“We use many signals to decide which title to show to users, primarily the <title> tag if the webmaster specified one,” he continues. “But for some pages, a single title might not be the best one to show for all queries, and so we have algorithms that generate alternative titles to make it easier for our users to recognize relevant pages. Our testing has shown that these alternative titles are generally more relevant to the query and can substantially improve the clickthrough rate to the result, helping both our searchers and webmasters. About half of the time, this is the reason we show an alternative title.”

“Other times, alternative titles are displayed for pages that have no title or a non-descriptive title specified by the webmaster in the HTML,” he adds. “For example, a title using simply the word “Home” is not really indicative of what the page is about. Another common issue we see is when a webmaster uses the same title on almost all of a website’s pages, sometimes exactly duplicating it and sometimes using only minor variations. Lastly, we also try to replace unnecessarily long or hard-to-read titles with more concise and descriptive alternatives.”

Far refers readers to a Google Help Center article about site titles and descriptions, which includes this video from Matt Cutts talking about titles and snippets:

In the help center article, Google says to make sure very page on your stie has a title tag, that they’re descriptive and concise, to avoid keyword stuffing and repeated or boilerplate titles, an to brand your titles (concisely).

“If we’ve detected that a particular result has one of the above issues with its title, we may try to generate an improved title from anchors, on-page text, or other sources,” Google says. “However, sometimes even pages with well-formulated, concise, descriptive titles will end up with different titles in our search results to better indicate their relevance to the query. There’s a simple reason for this: the title tag as specified by a webmaster is limited to being static, fixed regardless of the query. Once we know the user’s query, we can often find alternative text from a page that better explains why that result is relevant. Using this alternative text as a title helps the user, and it also can help your site. Users are scanning for their query terms or other signs of relevance in the results, and a title that is tailored for the query can increase the chances that they will click through.”

If you don’t like the way Google has re-titled your pages, you can let them know in the Webmaster Help Forum.

On Google+, Far highlighted two main takeaways for webmasters from all of this:

1. Our algorithms generate thee alternative titles so that your page is no longer constrained with having just the one title for all the different queries your page ranks for. This has the nice side effect of making the result look more relevant to our searchers and…

2. … On average, the alternative titles increase the clickthrough rate on the results, i.e. more traffic for you.

“The <title> tag is still a primary source for titles we show so all our advice about make them concise and useful and enticing still very much apply,” he says. “Keep an eye on the HTML Suggestions page in the Diagnostics section in Webmaster Tools for title suggestions.”

Have you noticed Google changing your titles? Are they being improved?