相同内容的a.html与b.html页面：Canonical URL元标签放置及写法咨询

Great question! When you’ve got two identical pages, the canonical URL tag is your go-to tool to avoid duplicate content issues and tell search engines which version you want them to prioritize. Here’s exactly how to implement it:

Where to Place the Tag #

First, pick one page as your primary, preferred canonical version—let’s say you choose a.html (you could just as easily pick b.html; the logic stays the same). Then:

• On your preferred page (a.html): Add a self-referential canonical tag. This reinforces to search engines that this is the main page they should index and rank.
• On the duplicate page (b.html): Add a canonical tag pointing directly to a.html. This tells search engines to treat b.html as a copy of your preferred page, so they won’t index it separately or split ranking signals between the two.

Correct Syntax #

Both tags need to live inside the <head> section of each HTML file. Always use the full absolute URL (including https:// and your domain name) for the href value—it’s far more reliable for search engines to parse correctly.

For a.html: #

<link rel="canonical" href="https://yourdomain.com/a.html">

For b.html: #

<link rel="canonical" href="https://yourdomain.com/a.html">

If you’d chosen b.html as the canonical instead, just swap the href value to point to b.html on both pages.

内容的提问来源于stack exchange，提问作者Webengineer