Creating valid HTML email newsletters and announcements with a canonical link element may help marketers boost search engine optimization.
The canonical link element, which is often referred to as rel=”canonical,” (pronounced rel canonical, no “equals”) is a way of describing the preferred URL for some particular web page. Search engines, including Google, Bing, and Yahoo!, all respect this element and will typically favor the specified canonical link in search results. Since December 2009, most search engines have allowed the canonical link to point across domains, so that a page on example.com could point to — and therefore transfer any SEO benefits to — a page on sample.com.
For the most part, the canonical link element has been used to avoid confusing search engines with duplicate content within a domain or on related sites. A search engine like Google would see www.example.com, example.com, example.com/, and example.com/index.html as four separate pages even though the web server points each to the same content.
During a recent episode of the respected Marketing Over Coffee podcast, Christopher Penn suggested using rel=”canonical” in HTML email newsletters or announcements because of the popularity of “view in browser” links that open an email’s content as a web page on the email service provider’s site.
Penn is vice president of strategy and innovation at Blue Sky Factory, an email and social marketing firm, the author of the book Marketing White Belt: Basics for the Digital Marketer, and one of the foremost experts on email marketing.
Adding a Canonical Link
Adding a canonical link to an HTML email, requires that the email include common HTML structures like a document type declaration, and a <head>
tag. Within the head tag, the marketer should add a link like the one below.
<link rel="canonical" href="http://www.yourdomain.com/email-landing-page.html"/>
With this link in place when a subscriber clicks on a “view in browser” link and is taken to a page on the email service provider’s site, any SEO benefit is forwarded to the URL specified in the href attribute of the canonical link element. The technique really is that easy.
Underlying Assumptions
Penn’s suggestion makes at least three underlying assumptions.
First, it assumes that using a complete and valid HTML document for HTML emails is a good idea. This assumption runs counter to the opinion of some email service providers, which claim that HTML meta data, including the contents of a <head>
tag, is a form of content spam. Penn obviously disagrees.
“Most spam checking things are worthless…most spam stuff that is being done today is at the domain level, at the IP level, at the reputation level. Content filtering with the exception of a few corporate systems…really doesn’t apply anymore,” Penn said.
Penn’s remarks do stand to reason, particularly with the rise of better email readers, mobile devices whose users may be more likely to view the message as a browser, and the continued drive toward email standards.
Next, Penn assumes that marketers will provide a relevant landing page worthy of the canonical link. This means that marketers will need to reproduce the email message content on their own server. One way to do this would be to have a newsletter archive section on site. Such a section is a good way to garner new subscribers and an obvious choice for a canonical link.
Third, Penn is assuming that any SEO benefit is actually worth the effort. Presumably, the SEO benefit would come from email subscribers who clicked the “view in browser” link; liked the content so well that they copy the page URL (remember this URL will probably be on the email service provider’s site); and then paste that link into a blog post, Twitter tweet, or a Google+ post.
Summing Up
I’ll summarize this article with a sample of Penn’s own words about the topic.
“I would make it a fully valid piece of HTML because what happens in a lot of cases is, especially with the bigger systems out there the more enterprise systems there is always a view in browser option…that goes to a page that then is effectively a web page. You can do one of two things with that: you can either user your own URL, which I would recommend — have it hosted on your site so you get the link juice…or at the very least use the full data structure and then put a rel=”canonical” back to your website so that your email service provider doesn’t suck up all of the SEO. But either way you need to have valid HTML in order to pull it off.”