A domain name is case-insensitive, but a path may be case-sensitive. /Service/ and /service/ can return different responses. Check the application before converting the entire website to lowercase.
Choose the address that should remain
Fictional example: old menu links use /Consultation/, while the CMS now generates /consultation/. Both show the same content. Establish which spelling belongs in the maintained page structure.
Request both variants directly and record the status, redirect destination and canonical URL. Compare their sitemap entries and internal links. Consistent output prevents new links from continually reintroducing the unwanted spelling.
If the variants serve different content, establish ownership of those pages first. A blanket lowercase rule could merge resources that must remain separate.
Include files and parameters in the review
An image named TeamPhoto.webp may require that exact spelling on another server. Identifiers or tokens in query parameters can also be case-sensitive. Restrict normalization to page paths for which it is intended.
Check the change using an old URL, the chosen destination and an existing file. The destination should remain directly accessible. Define a slug convention in the CMS for new pages so that each new article does not recreate the same mismatch.
Related check: Check a canonical redirect destination.
A defined path convention can be implemented in existing frontend output through scoped Frontend optimisation.