Low impactIndexing & crawl
URLs With Underscores
Google treats underscores as word joiners, not separators. Use hyphens instead.
What it means
URLs that use underscores (my_page) instead of hyphens (my-page) as word separators.
Why it matters
Google explicitly says hyphens are word separators while underscores are joiners. 'my_page' is read as one word 'mypage', bad for keyword matching.
How to fix it
- For new URLs always use hyphens.
- For existing underscore URLs: 301 redirect to hyphenated equivalents.
- Don't bulk-rename without redirects, you'll lose all link equity.
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Frequently asked questions
Will switching break anything?
Only if you skip the 301 redirects. With them, you keep equity.