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Report for stackoverflow.com


  • screenshot of stackoverflow.com
  • Score:


    Generated on Tuesday, May 24th 2016 6:07 pm

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Traffic Rank

49 most visited website in the World Trend: down (+8)
18 most visited website in IN India
Traffic Rank is provided by Alexa

Visitors Localization

Low map legend High
CountryPercentDomain (ccTLD)Status
IN India18.3%stackoverflow.inNot available.
US United States15.4%stackoverflow.usNot available.
CN China5.9%stackoverflow.cnNot available.
RU Russia5.0%stackoverflow.ruNot available.
KR South Korea3.8%stackoverflow.krNot available.
Registering country code top level domains (ccTLD) can prevent potential competitors from taking advantage of your primary domain reputation. It is also one of the ways to improve country specific SEO and performance. (http://www.searchenginejournal.com/seo-without-boarders-a-guide-to-international-seo-nick-paterman/60092/)


We have located images with missing ALT attribute.
Number of images: 11
Missing alt tag: 11

List of images with missing ALT attributes:

  • //i.stack.imgur.com/tKsDb.png (5 locations)
  • //i.stack.imgur.com/xKsQb.png (2 locations)
  • //i.stack.imgur.com/EdUwb.png
  • //i.stack.imgur.com/uE37r.png
  • //i.stack.imgur.com/PVepA.png
  • http://pixel.quantserve.com/pixel/p-c1rF4kxgLUzNc.gif
The "alt" attribute provides a text equivalent for the image. If the browser cannot display an image the alt description will be given in its place. Furthermore, some visitors cannot see images as they might be blind in which the alt tag provides a valuable image description. Finally, search engines utilize the alt attribute for image search indexing. (www.w3.org/QA/Tips/altAttribute)


We have found following title:

"Stack Overflow"

Length: 14 characters
The <TITLE> element provides a short piece of text describing the document. The title is very important as it shows in the window title bars, bookmarks and search results. Title should be between 60 to 80 characters long. (www.w3.org/QA/Tips/good-titles)

Description Metatag

No Description Found.
The description attribute should provide a concise explanation of a Web page's content. Also, the description is often displayed on search engine results and can indirectly affect page ranking. (en.wikipedia.org/wiki/Meta_element#The_description_attribute)

Keywords Metatag

No Keywords Found.
The keywords attribute was utilized by search engines to provide more accurate search results. Due to the over usage and spamming the keywords attribute has been phased out and is no longer relevant. Google doesn't use the "keywords" meta tag in web search ranking.(googlewebmastercentral.blogspot.se/2009/09/google-does-not-use-keywords-meta-tag.html)

Text to HTML Ratio

The Text to HTML ratio is 14.31%
Original content is by far the single most important element to search engines. Low Text to HTML ratio indicates little content for search engines to index. We consider it to be good practice to have a Text to HTML ratio of at least 10% and ideal above 20%

Keyword Density & Consistency

Consistent Keywords % Density # Count T Title D Desc. H <H> A ALT B <b>
mins ago3.97%81-----
stack overflow0.54%111----
secs ago0.29%6-----
min ago0.29%6-----
stack exchange0.20%4--1--
frank van puffelen0.10%2-----
stack overflow careers0.10%2-----
highcharts data module0.05%1--1--
inside controller angularjs0.05%1--1--
using highcharts data0.05%1--1--
Keywords density and consistency are notable factors for optimal page SEO. Preferred keywords should have higher keywords density indicating their importance. Optimally, preferred keywords should also be consistently utilized in multiple essential areas of the page such as title, description meta tag, h1 through h6 headings, alt image attributes, backlinks and internal links anchor text. Keyword density of above 5% is a good indication that the word or phrase appears too many time in the content. (more information)


Yes, 1 inline frame(s) detected.
It is not recommended to use frames or iframes because they can cause problems for search engines. It is best to avoid frames and inline frames whenever possible (searchenginewatch.com/article/2064573/Search-Engines-and-Frames). If frames must be utilized consider <noframes> tag. (www.w3schools.com/tags/tag_noframes.asp).


No flash detected.
Flash and other reach-media technologies should primarily be utilized for decorative purposes. This makes your site more search engine friendly and improves accessibility (support.google.com/webmasters/bin/answer.py?hl=en&answer=72746#1).


  • 1 <H1>
    • Top Questions
  • 1 <H2>
    • Looking for more? Browse the complete list of questions, or popular tags. Help us answer unanswered questions.
  • 99 <H3>
    • current community
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  • 1 <H4>
    • Hot Network Questions
  • 0 <H5>
  • 0 <H6>
The <h1> to <h6> tags are used to define HTML headings. The <h1> tag should hold the title describing the content of a specific page therefore only one h1 tag is needed per page. There can be any number of h2 - h6 tags but they should be added in order of importance (www.w3schools.com/tags/tag_hn.asp).


The <!DOCTYPE> declaration tells the web browser about what version of HTML the page is written in. It is good practice to always add the <!DOCTYPE> declaration to the HTML documents, so that the browser knows what type of document to expect. (www.w3schools.com/tags/tag_DOCTYPE.asp)

Character Encoding

Not declared.
To display an HTML page correctly, the browser must know what character-set to use (en.wikipedia.org/wiki/Character_encodings_in_HTML).


Declared Language: None
Language Attribute: None
The HTML "lang" attributes and language metatag define the base language to be used for displaying text and characters on a Website. www.mcanerin.com/en/articles/meta-language.asp

W3C Markup Validation

Status: FAILED [11 errors, 0 warning(s)]
It is good practice to use valid HTML/XHTML markup as it ensures that the search engines can read the website correctly as well as it improves cross browser compatibility (W3C Markup Validation Service).

Deprecated HTML elements

Good, no deprecated elements found.
A deprecated element is one that has been outdated by newer constructs. Deprecated elements may become obsolete in future versions of HTML so it is recommended not to use them. (webdesign.about.com/od/htmltags/a/bltags_deprctag.htm)

Nested HTML Tables

Great, no nested tables detected.
In general it is not recommended to use nested tables or to utilize tables for page layout. Nested tables are known to cause performance issues due to increased HTML size and rendering time. It is better to use CSS layout instead.

Web Analytics

Yes, we have detected following web anlytics tools:
  • Google analytics icon Google™ Analytics
  • Quantcast analytics icon Quantcast™ Measure
Web Analytics Tools collect and measure information about visitor activity on a website. Well interpreted web traffic data is invaluable in determining a successfully web strategy and assessing the effectiveness of a website. At a minimum, we recommend to utilize at least one web analytics tool.


A robots.txt file restricts access to search engine robots that crawl the web. (www.robotstxt.org/robotstxt.html)

XML Sitemap

Found following XML sitemap(s):
Sitemaps inform search engines about pages available for crawling. In its simplest form, a Sitemap is an XML file that lists URLs for a site along with additional metadata about each URL. XML sitemap should help search engines to crawl the site more intelligently. (http://www.sitemaps.org/protocol.html)

Mobile Rendering

Mobile internet usage has been exceeding PC's since 2014 and growing so it is critical for pages to render correctly on mobile devices.

Mobile Optimization

Mobile PageSpeed analyzes webpages and evaluates its performance while providing suggestions on reducing page load times. Google is incorporating website speed in search ranking (http://www.mattcutts.com/blog/site-speed)

Mobile Experience

Mobile users have now become a critical part of online visits. Making the website mobile friendly is no longer an option but rather necessity. (https://developers.google.com/webmasters/smartphone-sites/)


The Favicon is a small icon associated with a website. The Favicon is important because it is displayed next to the website's URL in the address bar of the browser as well as in bookmarks and shortcuts. (en.wikipedia.org/wiki/Favicon)

Custom 404 Error Page

Yes, custom 404 error page detected.
A 404 is a standard http response code for a resource that cannot be located on the server. Webservers usually return a "404 Not Found" error page for non-existing pages. Unfortunately, these default error pages are very generic and a not very user friendly, therefore, using a custom 404 error page is highly recommended.

Process of returning http status code "200 OK" for a non-existent page or redirecting users to another url is called soft 404. Soft 404 errors are problematic for search engines and are not advisable. (https://support.google.com/webmasters/answer/181708)


Could not locate print-friendly CSS.
Print-friendly pages are designed to fit on an 8.5"x11" or A4 sheet and usually include only the content of the page, along with source information. (webdesign.about.com/od/printerfriendly/a/aa041403a.htm)

W3C CSS Validation

Status: FAILED [67 error(s)]
It is recommended to use valid CSS to ensure that the website displays correctly. (W3C CSS Validation Service).

Page Rank

PR: 0 out of 10 (Very Poor)
PageRank is Google's measure of the importance of a page. It is based on complex algorithmes evaluating page content, authority, keyword density, back links, traffic, demand and more. (en.wikipedia.org/wiki/PageRank)

Indexed Pages

Estimated number of pages indexed by Bing™: about 10
The higher number of indexed pages the more content search engines can index, which increases overall value of the website. (en.wikipedia.org/wiki/Search_engine_indexing)

Domain Age

Your domain was registerd for the first time: 12 years, 4 months, 28 days ago.
Age of the domain is one of the many signals that search engines utilize for ranking. Brand new domains generally have more difficult time to rank high for the first few months. (http://www.coconutheadphones.com/does-domain-agematter)

Domain Expiration

Your domain expires in: 7 months, 1 day, 5 hours.
Domain expiration far in to the future is considered a good practice as it promotes confidence in your website, decreases chances of losing domain and in certain cases might help with search engine ranking. (http://www.hover.com/blog/three-reasons-to-renew-your-domain-names-for-five-years)

IP Canonicalization

No, your site's IP does not redirect to stackoverflow.com.
Some web spiders index websites using IP as well as domain name which can cause duplicate content if there is no IP Canonicalization. (www.mattcutts.com/blog/seo-advice-url-canonicalization)

URL Canonicalization

Yes, both the www.stackoverflow.com and stackoverflow.com resolve to the same URL.
Domain name with WWW and without can be considered as different pages causing duplicate content for search engines. (www.mattcutts.com/blog/seo-advice-url-canonicalization)

Page Speed

Google Page Speed score: 87% (High)
Rq. Requests Hst. Hosts LT Load time Html Img Images JS JavaScript CSS F Flash O Other PS Page Size
43181.73s241.91 KB148.13 KB410.75 KB506.96 KB0 B2.29 KB1.28 MB

Avoid landing page redirects
Enable compression
Leverage browser caching
Reduce server response time
Minify CSS
Minify HTML
Minify JavaScript
Eliminate render-blocking JavaScript and CSS in above-the-fold content
Optimize images
Prioritize visible content

Subscribe for more details
PageSpeed analyzes webpages and evaluates its performance while providing suggestions on reducing page load times. Google is now incorporating website speed in search ranking (http://www.mattcutts.com/blog/site-speed)

Server Information

Server IP:
Server Location:
US -, -

Name Server 1:
cf-dns01.stackoverflow.com (
Name Server 2:
cf-dns02.stackoverflow.com (
Your server's IP address and location have minor impact on the country specific SEO. It is recommend to host the website in the country where the number of vistors is desired to be the highest. Search engines take the geolocation of a server into account. (http://www.youtube.com/watch?v=hXt23AXlJJU)


Issued To:
Common Name (CN):
Common Name (CN):
COMODO ECC Domain Validation Secure Server CA 2
Oranization (O):
Period of Validity
Begins On:
Expires On:
Google™ is now treating HTTPS as a ranking signal. HTTPS is a secure web protocol that allows for encrypted communication between website and the client. HTTPS protocol requires your website to have an SSL certificate, which can be purchased from a Certificate Authority (CA) or SSL vendor. (http://googleonlinesecurity.blogspot.in/2014/08/https-as-ranking-signal_6.html).

Safe Browsing

Safe Browsing is a service provided by Google that enables applications to check URLs against Google's constantly updated lists of suspected phishing and malware pages. (http://www.google.com/safebrowsing/diagnostic?site=stackoverflow.com)

Spam Blacklist

Good, your IP is not blacklisted.
Spammer directories provide lists of IPs from which spam distribution is reported. Emails sent from the blocked IPs are subject to closer scrutiny and are much less likely to be delivered. For email campaigns it is recommended to utilize professional email services to ensure that your website IP is not blocked. (www.stopforumspam.com)

Email Address Obfuscation

There is 1 email in plain text on the webpage:
  • [email protected]
It is recommended to obfuscate email addresses posted in public. This prevents email addresses from being automatically harvested by spam bots which helps to decrease number of unsolicited emails.

Directory Browsing

Great, your server has directory browsing disabled.
Protect Webserver directories from unwanted browsing. To enhance security, directory browsing should be disabled unless you have a specific reason to enable it. If you enable directory browsing, make sure that you only enable it on the particular directory or directories that you want to share. (http://technet.microsoft.com/en-us/library/cc731109)

Whois Privacy

No contact information available.
Whois Privacy is a service that prevents domain owner contact information from being displayed in the publicly available Whois records. This can help to cut down on unwanted spam but utilizing Whois privacy should be evaluated against business model and branding strategy.

Server Signature

Good, your server does not provide version information.
Attackers can utilize server signature versioning information to their advantage therefore it is recommended to disable it when possible. (Disable server signature for Apache or IIS).

Professionals that can help with your website:

Your NameCompany NameCity, United States+1 5555555555
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