Regex Editor & Tester

Matches Windows Security Identifier (SID) strings in the two most common NT Authority (5) forms: builtin groups like S-1-5-32-544 (Administrators) or S-1-5-32-545 (Users), and machine/domain account SIDs such as S-1-5-21-RID-RID-RID-RID. Commonly used to extract or validate SIDs from logs, ACLs, and registry data. Note that \d* allows empty sub-authorities, so stricter validation would use \d+.