Opportunity Technical SEO
URL contains uppercase letters
- Severity
- Opportunity
- Impact
- Low
- Effort to fix
- Medium
- Issue code
url_uppercase
Why it matters
URLs are case sensitive, so mixed case can create duplicate URLs and broken links when typed or shared.
How to fix it
Use lowercase URLs and 301 redirect uppercase versions to them.
What this means
The URL's path contains capital letters, for example /Products/Running-Shoes. The domain is not checked, because domain names are not case sensitive. Paths are: on most servers, /Products and /products are two different URLs.
Why it matters
- Duplicate URLs. If the server answers both cases with a 200, search engines can index two copies of the same page, and links to it get split between them.
- Broken links. On a case-sensitive server, a link typed in lowercase returns a 404.
- Typing and sharing. Mixed case is harder to read aloud, type and remember.
Some servers, such as IIS on Windows, ignore case and return the same page for every variation. That makes the duplicate problem worse, not better, unless one version is canonical.
How to fix it
- Pick lowercase as the standard for new URLs, in the CMS slug settings or routing rules.
- For existing uppercase URLs that earn traffic or links, 301 redirect each one to its lowercase version, and update internal links, canonical tags and the sitemap.
- If you cannot change the URLs, make sure each page's canonical tag points to the one case you use in links, and that the other cases redirect or return a 404.
Do not lowercase URLs without redirects. Every old link and bookmark would break.
Verify the fix
The URL Structure view in Pages lists every flagged URL. After the change, recrawl: redirected URLs move to Redirecting URL, and any internal links still using the old case show up as Links to redirecting internal URLs. See also Duplicate content and URL structure.
How it affects your score
Finding this issue on any page costs the Technical SEO score 0.5 points, plus up to 4 more depending on the share of crawled pages affected. A smaller improvement with a modest effect on its own.
Find the affected URLs
Open Crawl > Issues and pick URL contains uppercase letters. Each affected URL is listed with its evidence, and Copy URLs or Export URLs hands the list to a developer. The issue also appears in the Action Plan, ranked by impact (low) and effort (medium), and in the issues CSV under the code url_uppercase. After fixing, run a new audit and use Compare to confirm the URLs moved to fixed.