lookup

sid::lookup can be used to lookup an object by its SID or name. It has the following command line arguments:

/sid: the security identifier value to lookup
/name: the sAMAccountName of the account to lookup
/domain: the domain name. If not specified, the current domain will be used

mimikatz # sid::lookup /name:m3g9tr0n
Name  : m3g9tr0n
Type  : User
Domain: hacklab
SID   : S-1-5-21-2725560159-1428537199-2260736313-1730

mimikatz # sid::lookup /sid:S-1-5-21-2725560159-1428537199-2260736313-1730
SID   : S-1-5-21-2725560159-1428537199-2260736313-1730
Type  : User
Domain: hacklab
Name  : m3g9tr0n

mimikatz # sid::lookup /sid:S-1-5-21-2725560159-1428537199-2260736313
SID   : S-1-5-21-2725560159-1428537199-2260736313
Type  : Domain
Domain: hacklab
Name  :