Faceted Navigation and SEO

Faceted navigation is a way to sort through a lot of items (usually products on an ecommerce site) using filtering categories. For example, a website selling household items might allow you to indicate through filters that you are looking for a rug of a certain size, in a certain color, in a particular fabric, and within a certain price range.

Faceted navigation can be great for improving the usability of a company’s website. Customers can find what they’re looking for more easily, compare different products, and move more quickly through the sales funnel into a purchase.

How to make sure faceted navigation helps your SEO (and doesn’t hurt it)

Making sure that faceted navigation helps your SEO (and doesn’t harm your SEO!) requires some careful web strategy. Normally, any website feature that improves the experience of the user also benefits SEO. However, the way that faceted navigation organizes information on a website creates some consequences that—if left unaddressed—could actually hurt the website’s SEO.

The good news is that you can address these consequences to make sure that your customers can enjoy the ease of faceted navigation while your website maintains strong SEO. In this blog, I’m going to outline the potential consequences of faceted navigation, then list some of the options you have for preventing those consequences.

Consequence 1: Faceted navigation can create duplicate content.

Let’s go back to the example of buying a rug on a housewares website. When you apply the filter “gray rugs under $150” you may get almost the same results as “gray rugs that are 48”x 24.” Similarly, if you’re shopping on a clothing website and filter “black dress, size small” or “black dress, size medium” you may get a lot of the same results (which means that the pages have similar content).

The problem is that even though many of the results for those combinations are the same, there is a unique URL for each combination of filters. Having multiple URLs with the same content is duplicate content.

So what can you do to keep search engines from viewing your site as having duplicate content due to faceted navigation?

• Use noindex, nofollow robots meta tags on pages. When you use this tag, it keeps these URLs from being indexed and appearing in search results. Because the pages aren’t indexed, they aren’t considered as harmful duplicate content.
• Use canonical tags. These tags signal that a page is a subcategory under a more important category. For example, this tag would contain the page URL you want the engines to ‘favor’, and it signals to search engines why you have duplicate content.
• Indicate in the robots.txt file that crawlers shouldn’t crawl certain pages. If the pages are marked that they shouldn’t be crawled, then it’s less likely that you’d be penalized for duplicate content.

That said, the pages can still be indexed if they’re linked to, so often I recommend using both the noindex, nofollow robots meta tag as well as a disallow in robots.txt.

Consequence 2: Faceted navigation uses up your crawl budget.

Your crawl budget is basically the amount of pages a search engine allocates to crawling on your site every day. You want search engines to crawl your site and find all the great content. The problem is that faceted navigation creates so many unique pages on your site that it can take up all the crawler’s time (and take it away from crawling the most important content, such as your great blogs).

So what can you do to keep search engines from using up your crawl budget on all the pages created by faceted navigation?

• Note that certain pages shouldn’t be crawled in your robots.txt file. If you tell the search engines not to crawl the pages, they won't, and your crawl budget is spared!
• Use nofollow internal links. By marking unimportant internal links as nofollow, you can keep bots from crawling unimportant pages.

Consequence 3: Faceted navigation can compromise the link equity of your pages.

Link equity is the value assigned to a page based on the links that point to the page. A page has greater link equity if more authoritative and relevant sites or pages point to the page AND if more links in general point to the page.

So basically what you don’t want to do is:

1. Scatter your link equity around among small and specific URLs in your domain when it could be consolidated to greater effect. If you take this back to the rug example, you don’t want the value of one popular lifestyle blogger to linking to a URL on red living room rugs made of wool under $150 to be separated from the value of an interior design firm linking to gray living room rugs made of cotton under $500. It would be better to get all the equity of those links to point to one, common place so that you have one page with really strong link equity rather than a few smaller pages with “okay” link equity.
2. Trap the value of link equity to a very specific URL in your domain. In rug example terms, if your URL that points to teal, wool rugs under $200 is getting all kinds of links, you don’t want to contain the value of that to just that URL. You want it to spill over onto your site!

So what can you do to get the most value from your links when you’re using faceted navigation?

• Use canonicalization. When it’s clear that a bunch of subcategories point to a larger category, the link equity from more specific URLs gets directed to the more general URLs.

Note that Noindex tags will allow pages to receive internal and external link equity, but it won’t consolidate it for larger effect. Nofollow tags will allow a page to receive external link equity but not internal link equity. Using robots.txt will trap and scatter link equity.

So now what should you do?

There’s no simple and perfect solution to accommodating faceted navigation on your website. Although one approach may address one concern, it may leave you vulnerable in another area.

The best way to decide what to do is rank the potential consequences of faceted navigation by how it would affect the business goals you have for your website. Then prioritize addressing the most important consequences for your business.

One other option you can consider if you have access to a web team or are considering rebuilding your website is using JavaScript to manipulate the number of URLs used in the filtering process of faceted navigation. Although this is more complex and time consuming, it can be a great long-term solution to the consequences of faceted navigation, but must be done carefully to not adversely affect the SEO of the site.

No matter what you decide to do, know that choosing faceted navigation to improve the usability of your website (and consequently your customers’ experience) does not mean that you have to give up on SEO. You have options at your fingertips to help you benefit from the best of both worlds!