What is the Tenant Lookup?

Every Microsoft 365 organisation has a unique identifier called a Tenant ID (a GUID like 72f988bf-86f1-41af-91ab-2d7cd011db47) and one or more domain names (e.g. contoso.com). This tool lets you resolve either one to the other — useful for identifying an unknown organisation, verifying a partner tenant, or bulk-enriching a list of domains.

Enter a domain name or a Tenant GUID below, one per line, or upload a file. Results can be exported as CSV.

Manual lookup

Enter one identifier per line — tenant GUID or domain name.

File import

Upload a .txt, .csv or .xlsx file. First column, one identifier per row. Max 300 identifiers.

Drop file here or browse
.txt · .csv · .xlsx
Lookup history
Sign in to keep your history
Your lookups will be saved for 90 days and exportable as CSV.
Sign in