In a recent post on the Webmaster Central Blog, Google has unfolded some of the best and worst practices related to faceted navigation. According to the post, the biggest disadvantage with faceted navigation is that it creates several combinations of duplicative URLs. It debars the search engine to produce unique content and index a page correctly because the signals are thinned out between the duplicated versions.
In the blog post, Google suggests that an individual product page or a category page should have only one accessible URL which has a clear click path. This route should be accessible from the home page or the category page.
In order to resolve the issues related to faceted navigation and to make these sites more search friendly, Google has come up with a list of best and worst practices for faceted navigation:
Worst practices for faceted navigation:
- Instead of “key=value&” pairs, encoding non-standard URL for parameters, like commas or brackets. Software engineer on Google’s Crawling Team, Mehmet Aktuna, says, “Using non-standard encoding is just asking for trouble”
- Using directories or file paths instead of using parameters to list values that don’t change page content.
- The conversion of user-generated values into URL parameters. They are crawl-able and indexable but are not useful in search results.
- Illogical appending of URL parameters.
- Offering further filtering when there are no results.
Best practices for new faceted navigation sites:
- Determine which parameters are required to create at least one clear click-path to each product or page.
- Determine which parameters would be valuable to searchers and which would cause undesirable duplication
- Configure URLs that contain unnecessary parameters. Sort out the unnecessary URL parameters and ensure that they are not required to reach individual products.
- Avoid offering further filtering when there are no results.
- Add logic to the display of URL parameters
- Improve indexing of individual content pages with rel=“canonical” to the preferred version of a page. rel=”canonical” can be used across host names or domains.
- Improve indexing of paginated content by either Adding rel=”canonical” from individual component pages in the series to the category’s “view-all” page Or Using pagination markup with rel=“next” and rel=“prev” to consolidate indexing properties, such as links, from the component pages/URLs to the series as a whole.
- If you are using JavaScript to filter content, without updating the URL, be sure that there still are URLs on your site that searchers would find valuable.
- Include only canonical URLs in Site maps.
In case of the existing sites, Google recommends that the user should ensure the use of parameters with standard encoding and key=value pairs. Apart from the above mentioned practices, it is also suggested to verify that values that don’t change page content, such as session IDs, are implemented as standard key=value pairs and not directories.