Broken links on a web page are one of the main reasons that users submit comments and complaints about the operation of the website, so it makes sense for links to be checked regularly. A consistent link checking policy ensures that external links always work.
External links are more difficult to track than internal links because third-party websites may have changed their content management system (CMS) or may have updated a URL naming convention; in any case, an automatic redirect for older or modified URLs may not have been implemented, so it’s up to you to make sure dead and broken external links are fixed.
Now we are going to provide an overview of a tool that can be used to find external broken links in web page document files, and share links and short descriptions for additional link checking applications.
LinkChecker
LinkChecker is a free GPL licensed website validator maintained by Bastian Kleineidam, and the project can be found in the wummel / linkchecker GitHub repository. The latest version updated on December 24, 2013 is LinkChecker 8.5 and is available for download from the website as an exe, deb, or tar.xz file.
LinkChecker features include recursive and multi-threaded link checking and site tracking; supports a command line interface, a GUI client interface, or a CGI web interface; provides support for cookies and HTML5; and you can check the HTML and CSS syntax. The exe file downloads as LinkChecker-8.5.exe and takes just over 11M, and the simple installation takes less than a minute to complete.
Find the program in the list of installations and open the application.
You can check a document on a web page by entering a fully qualified URL in the GUI client or web interface (that is, http://www.domainname.com), and then pressing the start button at the bottom. Upper right. Link checking will recursively validate all pages starting with the main URL; All external links pointing outside of the main URL will be checked, but recursive checking will not be used for external third party web pages. For more information and details on options, settings, output types, proxy support, and other topics, see the online manual.
Checking for links on the example page http://wummel.github.io/linkchecker/index.html resulted in 48 URLs found, 12 warnings, and 0 invalid URLs. The URL properties for the first prominent parent URL http://wummel.github.io/linkchecker/faq.html shows a warning of a redirect that must be updated from line 74 of the faq.html file to a link to http://seleniumhq.org, which eventually redirects to http://docs.seleniumhq.org/. Although the redirect works in this case, it’s probably a good idea for Bastian to update the link on the page so as not to rely on Selenium’s due diligence to keep the redirect active.
Additional link-checking applications
Xenu
Xenu is a free download tool from Tilman Hausherr and is registered as Xenu, Xenu’s Link Sleuth, and Link Sleuth for software products and services. The latest functional software download is version 1.3.8 from September 4, 2010. For more information, see the official description page.
W3C Link Checker
With W3C’s free link checker, you enter a URL in the form field and you get the options of summary only, hiding redirects for all or directories only, and checking recursively linked documents within an assigned depth. Also, you can save link checking options as a cookie.
What do you use to check external links?
What link checking tool do you use for your websites? Let us know in the comment section.
