Download websites that use Microsoft 365

About Microsoft 365

Microsoft 365 is not one product, and a detection almost never proves you have found all of it. The brand covers mail, file storage, collaboration, telephony, identity and a growing pile of adjacent services, while the evidence that reaches a crawler is usually a single narrow artefact: a mail exchange record, an identity endpoint, a federation hint left in the domain's name server configuration. From the outside we can say a tenant exists behind a domain. Which components that tenant actually pays for is a separate question, and the data does not answer it.

Identity is where the interesting consequences sit. A tenant is not only a mailbox estate, it is also the directory that third party applications authenticate against, which means the same record marks the domains where single sign on integrations, application consent policies and conditional access rules are in play. For anyone selling software that plugs into a corporate directory, a tenant record is a qualification signal about integration path and procurement route rather than merely a note about email.

The suite from Microsoft has been sold as Proprietary software since 2011, long enough that a substantial part of the estate predates the current branding and arrived through renewals rather than through fresh decisions. As of September 2026 we detect it on 15,344,211 domains, 9,112,430 of them in United States, with the list skewing toward .com.

Concentration in one country reflects where large organisations register their primary domains, not where their staff sit. A multinational may run a single tenant for offices spread across many countries, so a country column on this row measures corporate registration and headquarters geography rather than headcount. Reading the breakdown as a map of users will mislead you. Reading it as a map of buying entities will not.

Independent software vendors, migration consultancies, backup and archiving providers, security teams modelling credential phishing surface and analysts tracking the office suite split all want the same thing, which is a population rather than a lookup. One domain can be resolved by anyone in moments. What cannot be improvised is the reverse view, where you start from a filter, say every domain in one country under one suffix that shows this tenant and also runs a particular ecommerce or content management stack, and get back rows ready to load into a sales system.

Limits are real and we would rather state them than have you discover them later. Detection is inferential, resellers and syndication partners blur who the paying customer actually is, split domain configurations are common inside large groups, and nothing in the record indicates seat count, licence tier or contract date. Movement between suites is quiet and continuous, so a file bought today describes a moment rather than a settled state. Used as a starting universe that you then qualify, the row is dependable. Used as a headcount or a revenue estimate, it will let you down, and no amount of careful filtering afterwards can recover a number the crawl never contained.