What it is
URLs are case-sensitive after the domain, so /Page and /page can be treated as two different URLs. Mixed case invites accidental duplicates. Mixed-case paths. Case sensitivity can create duplicate URLs. Use lowercase; redirect variants. Low-medium. Inferred.
Why does uppercase characters in urls matter for AI search?
Case sensitivity can create duplicate URLs.
How do you fix it?
Use lowercase; redirect variants.
How do you find it on your site?
- Check whether your URLs contain uppercase characters.
- Test whether the uppercase and lowercase versions both resolve to 200.
- Standardise on lowercase and redirect uppercase variants.
- Add a server rule to lowercase incoming paths if needed.
Which ranking and citation factors does it touch?
Case-variant duplicates split signals across what should be one URL. Lowercasing consistently avoids the duplication.
What is the impact?
Low-medium. Inferred.
What is the evidence?
Consistent (lowercase) URLs avoid duplication. Google Search Central, Keep a simple URL structure; Google Search Central, Consolidate duplicate URLs (canonicalization)
Sources
Frequently asked questions about uppercase characters in urls
What does "Uppercase characters in URLs" mean?
Mixed-case paths.
How do you fix uppercase characters in URLs?
Use lowercase; redirect variants.