Can TLDs be case sensitive?

No, Top-Level Domains (TLDs) cannot be case sensitive. In the Domain Name System (DNS), TLDs are treated as case-insensitive, meaning that upper and lower case letters are considered identical when resolving domain names. This applies to both generic TLDs (gTLDs) like .com, .org, .net, etc., and country code TLDs (ccTLDs) like .us, .uk, .ca, etc.

For example, when you type a domain name or TLD in a web browser or enter it in any DNS-related query, the system automatically converts all letters to lowercase before processing. This ensures uniformity and consistency in resolving domain names, regardless of the case used by the user.

Therefore, whether you type ".COM" or ".com," the DNS system treats both inputs as identical and resolves them to the same TLD. This case-insensitive behavior simplifies domain name management and prevents potential confusion or errors caused by case variations.