Webmaster Level: intermediate

Mobile is growing at a fantastic pace – in usage, not just in screen size. To keep you informed of issues mobile users might be seeing across your website, we’ve added the Mobile Usability feature to Webmaster Tools.

The new feature shows mobile usability issues we’ve identified across your website, complete with graphs over time so that you see the progress that you’ve made.

A mobile-friendly site is one that you can easily read & use on a smartphone, by only having to scroll up or down. Swiping left/right to search for content, zooming to read text and use UI elements, or not being able to see the content at all make a site harder to use for users on mobile phones. To help, the Mobile Usability reports show the following issues: Flash content, missing viewport (a critical meta-tag for mobile pages), tiny fonts, fixed-width viewports, content not sized to viewport, and clickable links/buttons too close to each other.

We strongly recommend you take a look at these issues in Webmaster Tools, and think about how they might be resolved; sometimes it’s just a matter of tweaking your site’s template! More information on how to make a great mobile-friendly website can be found in our Web Fundamentals website (with more information to come soon).

If you have any questions, feel free to join us in our webmaster help forums (on your phone too)!

Posted by John Mueller, Webmaster Trends Analyst, Zurich

Webmaster level: intermediate-advanced

Submitting sitemaps can be an important part of optimizing websites. Sitemaps enable search engines to discover all pages on a site and to download them quickly when they change. This blog post explains which fields in sitemaps are important, when to use XML sitemaps and RSS/Atom feeds, and how to optimize them for Google.

Sitemaps and feeds

Sitemaps can be in XML sitemap, RSS, or Atom formats. The important difference between these formats is that XML sitemaps describe the whole set of URLs within a site, while RSS/Atom feeds describe recent changes. This has important implications:

• XML sitemaps are usually large; RSS/Atom feeds are small, containing only the most recent updates to your site.
• XML sitemaps are downloaded less frequently than RSS/Atom feeds.

For optimal crawling, we recommend using both XML sitemaps and RSS/Atom feeds. XML sitemaps will give Google information about all of the pages on your site. RSS/Atom feeds will provide all updates on your site, helping Google to keep your content fresher in its index. Note that submitting sitemaps or feeds does not guarantee the indexing of those URLs.

Example of an XML sitemap:

<?xml version="1.0" encoding="utf-8"?>
<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
 <url>
   <loc>http://example.com/mypage</loc>
   <lastmod>2011-06-27T19:34:00+01:00</lastmod>
   <!-- optional additional tags -->
 </url>
 <url>
   ...
 </url>
</urlset>

Example of an RSS feed:

<?xml version="1.0" encoding="utf-8"?>
<rss>
 <channel>
   <!-- other tags -->
   <item>
     <!-- other tags -->
     <link>http://example.com/mypage</link>
     <pubDate>Mon, 27 Jun 2011 19:34:00 +0100</pubDate>
   </item>
   <item>
     ...
   </item>
 </channel>
</rss>

Example of an Atom feed:

<?xml version="1.0" encoding="utf-8"?>
<feed xmlns="http://www.w3.org/2005/Atom">
 <!-- other tags -->
 <entry>
   <link href="http://example.com/mypage" />
   <updated>2011-06-27T19:34:00+01:00</updated>
   <!-- other tags -->
 </entry>
 <entry>
   ...
 </entry>
</feed>

“other tags” refer to both optional and required tags by their respective standards. We recommend that you specify the required tags for Atom/RSS as they will help you to appear on other properties that might use these feeds, in addition to Google Search.

Best practices

Important fields

XML sitemaps and RSS/Atom feeds, in their core, are lists of URLs with metadata attached to them. The two most important pieces of information for Google are the URL itself and its last modification time:

URLs

URLs in XML sitemaps and RSS/Atom feeds should adhere to the following guidelines:

• Only include URLs that can be fetched by Googlebot. A common mistake is including URLs disallowed by robots.txt — which cannot be fetched by Googlebot, or including URLs of pages that don’t exist.
• Only include canonical URLs. A common mistake is to include URLs of duplicate pages. This increases the load on your server without improving indexing.

Last modification time

Specify a last modification time for each URL in an XML sitemap and RSS/Atom feed. The last modification time should be the last time the content of the page changed meaningfully. If a change is meant to be visible in the search results, then the last modification time should be the time of this change.

• XML sitemap uses  <lastmod>
• RSS uses <pubDate>
• Atom uses <updated>

Be sure to set or update last modification time correctly:

• Specify the time in the correct format: W3C Datetime for XML sitemaps, RFC3339 for Atom and RFC822 for RSS.
• Only update modification time when the content changed meaningfully.
• Don’t set the last modification time to the current time whenever the sitemap or feed is served.

XML sitemaps

XML sitemaps should contain URLs of all pages on your site. They are often large and update infrequently. Follow these guidelines:

• For a single XML sitemap: update it at least once a day (if your site changes regularly) and ping Google after you update it.
• For a set of XML sitemaps: maximize the number of URLs in each XML sitemap. The limit is 50,000 URLs or a maximum size of 10MB uncompressed, whichever is reached first. Ping Google for each updated XML sitemap (or once for the sitemap index, if that’s used) every time it is updated. A common mistake is to put only a handful of URLs into each XML sitemap file, which usually makes it harder for Google to download all of these XML sitemaps in a reasonable time.

RSS/Atom

RSS/Atom feeds should convey recent updates of your site. They are usually small and updated frequently. For these feeds, we recommend:

• When a new page is added or an existing page meaningfully changed, add the URL and the modification time to the feed.
• In order for Google to not miss updates, the RSS/Atom feed should have all updates in it since at least the last time Google downloaded it. The best way to achieve this is by using PubSubHubbub. The hub will propagate the content of your feed to all interested parties (RSS readers, search engines, etc.) in the fastest and most efficient way possible.

Generating both XML sitemaps and Atom/RSS feeds is a great way to optimize crawling of a site for Google and other search engines. The key information in these files is the canonical URL and the time of the last modification of pages within the website. Setting these properly, and notifying Google and other search engines through sitemaps pings and PubSubHubbub, will allow your website to be crawled optimally, and represented accordingly in search results.

If you have any questions, feel free to post them here, or to join other webmasters in the webmaster help forum section on sitemaps.

Posted by Alkis Evlogimenos, Google Feeds Team

Webmaster level: All

This June, we introduced a weeklong social campaign called #NoHacked. The goals for #NoHacked are to bring awareness to hacking attacks and offer tips on how to keep your sites safe from hackers.

We held the campaign in 11 languages on multiple channels including Google+, Twitter and Weibo. About 1 million people viewed our tips and hundreds of users used the hashtag #NoHacked to spread awareness and to share their own tips. Check them out below!

Posts we shared during the campaign:

https://plus.google.com/+GoogleWebmasters/posts/1BzXjgJMGFU

https://plus.google.com/+GoogleWebmasters/posts/TMhfwQG3p8P

https://plus.google.com/+GoogleWebmasters/posts/AcUS4WhF6LL

https://plus.google.com/+GoogleWebmasters/posts/DUTpSGmkBUP

https://plus.google.com/+GoogleWebmasters/posts/UjZRbySM5gM

Some of the many tips shared by users across the globe:

• Pablo Silvio Esquivel from Brazil recommends users not to use pirated software (source)
• Rens Blom from the Netherlands suggests using different passwords for your accounts, changing them regularly, and using an extra layer of security such as two-step authentication (source)
• Дмитрий Комягин from Russia says to regularly monitor traffic sources, search queries and landing pages, and to look out for spikes in traffic (source)
• 工務店コンサルタント from Japan advises everyone to choose a good hosting company that’s knowledgeable in hacking issues and to set email forwarding in Webmaster Tools (source)
• Kamil Guzdek from Poland advocates changing the default table prefix in wp-config to a custom one when installing a new WordPress to lower the risk of the database from being hacked (source)

Hacking is still a surprisingly common issue around the world so we highly encourage all webmasters to follow these useful tips. Feel free to continue using the hashtag #NoHacked to share your own tips or experiences around hacking prevention and awareness. Thanks for supporting the #NoHacked campaign!

And in the unfortunate event that your site gets hacked, we’ll help you toward a speedy and thorough recovery:

• Follow these steps towards recovery
• Post a question or search for answers in our Help Forum

Posted by your friendly #NoHacked helpers

Webmaster level: all

Security is a top priority for Google. We invest a lot in making sure that our services use industry-leading security, like strong HTTPS encryption by default. That means that people using Search, Gmail and Google Drive, for example, automatically have a secure connection to Google.

Beyond our own stuff, we’re also working to make the Internet safer more broadly. A big part of that is making sure that websites people access from Google are secure. For instance, we have created resources to help webmasters prevent and fix security breaches on their sites.

We want to go even further. At Google I/O a few months ago, we called for “HTTPS everywhere” on the web.

We’ve also seen more and more webmasters adopting HTTPS (also known as HTTP over TLS, or Transport Layer Security), on their website, which is encouraging.

For these reasons, over the past few months we’ve been running tests taking into account whether sites use secure, encrypted connections as a signal in our search ranking algorithms. We’ve seen positive results, so we’re starting to use HTTPS as a ranking signal. For now it’s only a very lightweight signal — affecting fewer than 1% of global queries, and carrying less weight than other signals such as high-quality content — while we give webmasters time to switch to HTTPS. But over time, we may decide to strengthen it, because we’d like to encourage all website owners to switch from HTTP to HTTPS to keep everyone safe on the web.

In the coming weeks, we’ll publish detailed best practices (it’s in our help center now) to make TLS adoption easier, and to avoid common mistakes. Here are some basic tips to get started:

• Decide the kind of certificate you need: single, multi-domain, or wildcard certificate
• Use 2048-bit key certificates
• Use relative URLs for resources that reside on the same secure domain
• Use protocol relative URLs for all other domains
• Check out our Site move article for more guidelines on how to change your website’s address
• Don’t block your HTTPS site from crawling using robots.txt
• Allow indexing of your pages by search engines where possible. Avoid the noindex robots meta tag.

If your website is already serving on HTTPS, you can test its security level and configuration with the Qualys Lab tool. If you are concerned about TLS and your site’s performance, have a look at Is TLS fast yet?. And of course, if you have any questions or concerns, please feel free to post in our Webmaster Help Forums.

We hope to see more websites using HTTPS in the future. Let’s all make the web more secure!

Posted by Zineb Ait Bahajji and Gary Illyes, Webmaster Trends Analysts

Webmaster level: intermediate-advanced

To crawl, or not to crawl, that is the robots.txt question.

Making and maintaining correct robots.txt files can sometimes be difficult. While most sites have it easy (tip: they often don’t even need a robots.txt file!), finding the directives within a large robots.txt file that are or were blocking individual URLs can be quite tricky. To make that easier, we’re now announcing an updated robots.txt testing tool in Webmaster Tools.

You can find the updated testing tool in Webmaster Tools within the Crawl section:

Here you’ll see the current robots.txt file, and can test new URLs to see whether they’re disallowed for crawling. To guide your way through complicated directives, it will highlight the specific one that led to the final decision. You can make changes in the file and test those too, you’ll just need to upload the new version of the file to your server afterwards to make the changes take effect. Our developers site has more about robots.txt directives and how the files are processed.

Additionally, you’ll be able to review older versions of your robots.txt file, and see when access issues block us from crawling. For example, if Googlebot sees a 500 server error for the robots.txt file, we’ll generally pause further crawling of the website.

Since there may be some errors or warnings shown for your existing sites, we recommend double-checking their robots.txt files. You can also combine it with other parts of Webmaster Tools: for example, you might use the updated Fetch as Google tool to render important pages on your website. If any blocked URLs are reported, you can use this robots.txt tester to find the directive that’s blocking them, and, of course, then improve that. A common problem we’ve seen comes from old robots.txt files that block CSS, JavaScript, or mobile content — fixing that is often trivial once you’ve seen it.

We hope this updated tool makes it easier for you to test & maintain the robots.txt file. Should you have any questions, or need help with crafting a good set of directives, feel free to drop by our webmaster’s help forum!

Posted by Asaph Arnon, Webmaster Tools team

Webmaster Level: AllRedirects are often used by webmasters to help forward visitors from one page to another. They are a normal part of how the web operates, and are very valuable when well used. However, some redirects are designed to manipulate or de…