For a fashion E-commerce retailer, layered navigation seems like a no-brainer. With an extensive product range spanning potentially hundreds of brands and clothing types, colours and sizes your users really need some way of paring down their list of choices to isolate the kind of item they’re looking to purchase. Offering this great degree of choice to potential customers, however, can thrust a site into a whole new arena of problematic SEO issues.
A sizeable list of filters or attributes to choose from might look inconsequential to a visitor, but to a search engine crawler it may be a labyrinth of internal links it somehow has to claw its way through. With that in mind, how have some of the biggest fashion e-retailers dealt with this potential issue?
ASOS have pushed the boat out with their layered navigation, you can filter by style, type, size, colour, brand, price and item-specific options such as sleeve length. On a given category it adds up to an awful lot of links. So what tactics have they used to try and optimise this element of their navigation? For starters, each filter ‘tick-box’ has the rel=”nofollow” attribute appended to it. Our own investigations into this tactic have suggested that it might not be ideal – after all, rel=”nofollow” is intended for content that you as a webmaster aren’t able to vouch for – so does it make sense to use it here? Similarly, while a nofollow link won’t pass PageRank, it doesn’t necessarily store it up in the originating page either, it might just be lost.
Click on one of the filters and you’ll see that the URLs do change, and that they’re dynamically generated and based on query strings. To cut down on the number of indexed URLs they’ve used rel=”canonical” tags on these filtered pages, pointing back to the base category. Again, this isn’t strictly a bona fide use of the canonical tag, which is intended for pages where the content is identical – or near as damnit – in this instance, while the page title and copy on the page don’t change, the list of products is being considerably narrowed or changed.
Riverisland.com doesn’t have quite the range of filters that ASOS utilise, but it’s quite a list with subcategories, size, colour and price. The initial category URLs are very clean (e.g. http://www.riverisland.com/men/shirts) and clicking a filter applies a parameter to the end (e.g. http://www.riverisland.com/men/shirts?f_sizes=XXS) which initially looked rather tidy as well, but branching out and plumping to narrow my search to long-sleeved shirts took produced the URL http://www.riverisland.com/men/shirts?f_parent_category_names=b7685d07-b002-4cc1-a39f-b1bc88d4d13c. As with ASOS, each ‘filtered’ page is canonicalised back to the main category URL.
A key difference on this site is that at the top of each category page is a banner with links to the various sub-categories (in this instance shirts) – but rather than being dynamic, parameter-based URLs these are static pages (e.g. http://www.riverisland.com/men/shirts/long-sleeve-shirts) and it’s these pages that rank if we search for relevant terms in Google’s index.
Topman.com offers much the same choices as River Island, but with the added functionality of being able to sort items by customer review. Applying filters to your selection creates a huge, unwieldy URL, much of which is unreadable for most search engines – and on searching Google’s index for these pages, the URL that Google is picking up and indexing is completely different to the one that a user will end up on by going through the onsite navigation. Check out the two bit.ly links below and see the different in URL:
Accessing the long-sleeved shirt page through onsite navigation: http://bit.ly/ST9Q7k
The same page, accessed via Google’s cached version of the parent category: http://bit.ly/1joGIeW
The URLs Google is being served are much more search engine-friendly as only a small portion of the URL is parameter based and they’re able to include relevant keywords. As with the two other sites, canonical tags are in place and referring back to the main category URL.
Three similar sites, with close to identical-seeming navigation systems to a typical visitor, and yet each has taken a different approach to how they should serve up this content to search engines. I suspect that taking a look at another ten sites would reveal ten more strategies – none of the sites in this post have utilised META robots instructions or complicated cloaking techniques, for example, but I’m sure they’re out there in the fashion world.
Layered navigation is a tricky subject even for an experienced SEO, and it may be that rather than there being one ultimate strategy for optimisation, that it needs to be assessed on a case-by-case basis – with so many factors involved it’s often a case of clipping a site back to basics, assessing how and when your pages are being crawled by Google & Co. and then seeing what options are available to you in terms of opening the site up.