Canonical URL

flowchart LR

subgraph site[Your site]
/blog-post-1 --> /rss.xml
/rss.xml
end

/rss.xml --> Buttondown
Buttondown --> email["`**New blog post**
You'll never believe what happened next!`"]

email --> /blog-post-1

Let's say you're the CEO of Sheinhardt Wig Company. You have a robust and mature corporate blog at sheinhardtwig.com, but you want to send out all new blog posts as emails as well.

A standard workflow might involve you grabbing the content of your blog post (e.g. https://sheinhardtwig.com/2025/01/17/my-new-blog-post) and sending it out as an email to your subscribers. Buttondown will then create an archived version of that email to be shared on the web — at, say, https://buttondown.com/sheinhardtwig/archive/my-new-blog-post.

This has a couple problems:

• Google will index the archived version of your email in addition to the original blog post, potentially penalizing your overall traffic.
• Your blog — the original source of the content — might have additional content that you'd prefer your subscribers to see rather than Buttondown's archived version.

In order to more harmoniously integrate Buttondown with your existing content, Buttondown allows you to set a canonical URL for every email you send. Buttondown will surface this URL rather than its own archive URL in a number of places:

• In the email's header, so that your subscribers can click through to the original source of the content without going through Buttondown's archives.
• In the <meta> tags of the email's HTML, so that search engines index the original source of the content.
• In the RSS and archive pages, so that subscribers can click through to the original post from Buttondown's archives.

You can set a canonical URL in a number of ways:

• If you're using RSS-to-email, Buttondown will automatically set the canonical URL of every email to URL of the relevant RSS item.
• If you're using the API, you can set the Email.canonical_url field.
• If you're sending emails using the user interface, you can set the canonical URL in the "metadata" section when finalizing your email.