What is a mail provider?
A mail provider is the service that receives and stores a domain's email, such as Google Workspace or Microsoft 365. No single DNS record names it, so it is worked out from where the MX records point. The DNS host, the company running the domain's nameservers, is a separate role and often a different company.
Reading the result
You get the provider the MX hosts belong to, the DNS host behind the nameservers, and both raw lists so you can check the inference yourself. When a host belongs to no provider the tool knows, which is common for self-hosted servers, the raw names are still there to read.
Beat runs on the same engine, on a schedule, across all 41 checks and 25 blacklists. What it adds is asking again, noticing when an answer changes and telling you what to do about it.
Common mail provider mix-ups
MX hosts from two providers
Usually a migration left half done. Incoming mail is split between two systems, and whatever reaches the old one may never be read.
Editing DNS in the wrong place
If the nameservers belong to a different company from the one where you edit records, your changes never go live. The DNS host shown here is where SPF, DKIM and DMARC have to be published.
Mixing up the provider and your senders
The provider receives your mail. Every service that sends as you, from a newsletter tool to a cold-email platform, needs its own SPF include and DKIM key as well.