What is a canonical tag (URL canonicalization)?
A canonical tag is an HTML tag used to prevent duplicate content issues.
When the same website can be reached through multiple URLs, you can tell search engines which URL is the "canonical" one, so your pages aren't flagged as duplicate content.
For example, there are several ways to reach "https://studio.design/ja".
With a trailing slash: https://studio.design/ja
/With ad tracking parameters: https://studio.design/ja
?xxx
If Search Console treats each of these URLs as a separate site, it may see them as multiple pages with the same content (in other words, duplicate content), which can split your SEO value across them.
To prevent this, URLs like the ones above include a canonical tag that points to "https://studio.design/ja" as the canonical URL. This helps search engines identify the correct URL for the page and keeps your site's ranking signals consolidated.
How canonical tags work in Studio.Design
Studio.Design automatically determines the correct canonical URL based on the path of the page being viewed and adds a canonical tag for you. You can choose whether canonical tags include a trailing slash on a per-project basis.
You can't set this individually for each page or CMS item
If you don't change the setting, URLs are output without a trailing slash
The top page always includes a trailing slash, regardless of this setting
No canonical tag is generated for 404 pages
The canonical tag and the og:url tag use the same URL
Note: This setting only affects the canonical tag that's output. It doesn't redirect the URLs themselves.
How to set the trailing slash
Who can do this: the owner of the project
Note: This setting is only available for projects running on the new publishing infrastructure. For projects on the previous infrastructure, this option is locked and can't be changed.
Open the [Settings] tab in the dashboard of the project.
Open [General].
Click [Settings] under [Trailing Slash].
Choose whether to include a trailing slash, then click [Save].
How long it takes to take effect depends on when the cache is cleared.
Note: You can change and save this setting even while your site is unpublished, but the change won't actually take effect until you publish the site.
When the canonical tag is added
On sites published with Studio.Design, the canonical tag isn't included in the HTML returned by the server. It's added when the page is rendered in the browser.
HTML returned by the server—the HTML you see with your browser's "View Source" (view-source:). The canonical tag isn't included at this stage.
Rendered HTML—the HTML after it's been drawn by JavaScript, which you can check in your browser's developer tools. The canonical tag is included at this stage.
How canonical URLs are generated
Any hash included in the URL is removed
If you're using a custom proxy, the custom proxy domain is used as the host in the canonical tag
How this applies to your sitemap
The same trailing slash setting also applies to the URLs in your sitemap (sitemap.xml). This covers subpages and dynamic pages. The top page always includes a trailing slash, regardless of the setting.
For more details, see Sitemap.