If you ever wanted to know, if Googlebot has crawled and indexed your web pages? Now, you can get that question answered by just using the new "Index Status" feature launches today in the Google Webmaster Tools -- that will show you "how many pages from your site have been included in Google's index." Sound good!
Once logged in your Webmaster Tools account, you can find "Index Status" under the Health menu. After clicking on it you'll see a graph like the one pictured below -- and it shows how many pages are currently indexed. The legend shows the latest count and the graph shows up to one year of data.
If you see a steadily increasing number of indexed pages, congratulations! This should be enough to confirm that new content on your site is being discovered, crawled and indexed by Google.
As, some webmaster may find issues that require looking a little bit deeper, Google added an "Advanced tab" to the feature that can be accessed by clicking on the button at the top, and will "show not only totals of indexed pages, but also the cumulative number of pages crawled, the number of pages that we know about which are not crawled because they are blocked by robots.txt, and also the number of pages that were not selected for inclusion in our results," informs Google.
See the picture below: Notice that the counts are always totals. So, "for example, if on June 17th the count for indexed pages is 92, that means that there are a total of 92 pages indexed at this point in time, not that 92 pages were added to the index on that day only," Google explained.
In particular for sites with a long history, the count of pages crawled may be very big in comparison with the number of pages indexed. "All this data can be used to identify and debug a variety of indexing-related problems," Google stated.
For example, "if some of your content doesn't appear any more on Google and you notice that the graph of pages indexed has a sudden drop, that may be an indication that you introduced a site-wide error when using meta="noindex" and now Google isn't including your content in search results," Google explains.
Google citing another example explains, "if you change the URL structure of your site and don't follow the recommendations for moving your site, you may see a jump in the count of "Not selected". Fixing the redirects or rel="canonical" tags should help get better indexing coverage."