内部 SEO
canonical タグ
重要な理由
The canonical tag tells search engines which URL is the preferred version of a page. Without it, or with a wrong one, duplicate URLs (with parameters, http/https, www) can split signals or the wrong page can be indexed.
修正方法
- Add <link rel="canonical" href="…"> with the full preferred URL on every indexable page.
- Point it at the page itself unless the page is a true duplicate.
- Use only one canonical tag, and keep it the same in the raw HTML and after JavaScript runs.
次のツールで確認
- Canonical Tag Checker – Check a page’s canonical URL, whether it resolves, and if it conflicts with other signals.
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