IMAP and SMTP settings finder
Paste an address and this tells you which provider actually runs its mail, and the server settings that go with it. It is the same detection Mailbind’s connect screen uses.
The domain you type is used for the lookup and then forgotten: it is not stored and not written to any log. Only a count of how often the tool was used is kept.
How it works out the answer
Three steps, in order. First the domain itself: gmail.com, outlook.com, icloud.com and a handful of others are known outright. Then the domain’s MX records, which say which mail servers accept mail for it — this is the step that matters, because it recognises a custom domain whose mail is really at Microsoft 365, OVHcloud or Infomaniak. Finally, if nothing is recognised, it falls back to the conventional names a hosting provider usually uses for a domain.
The third case is a guess and the tool says so. A guess is often right, because mail.yourdomain.tld and imap.yourdomain.tld are conventions, but it is not evidence; check it against your provider’s own documentation before you type it into a client.
- Works from a full address or a bare domain.
- Names the provider when the records identify one.
- Shows the host, the port and the encryption for both directions.
- Says whether the answer came from the domain, from the MX records, or from a guess.
What the ports mean
Four ports carry almost all client mail, and the choice between them is about when encryption starts rather than how strong it is. 993 for IMAP and 465 for SMTP are implicit TLS: the connection is encrypted from the first byte. 143 for IMAP and 587 for SMTP start in the clear and upgrade with STARTTLS, which is equally secure once established but depends on the client insisting on the upgrade.
Prefer 993 and 465 where a provider offers them, and 587 where it recommends that instead — several do, because 587 is the submission standard. Never use 110 or 25 for a client: the first is unencrypted POP and the second is for server-to-server transfer.
| Protocol | Port | Encryption | Use |
|---|---|---|---|
| IMAP | 993 | Implicit TLS | Reading mail — preferred |
| IMAP | 143 | STARTTLS | Where 993 is unavailable |
| SMTP | 465 | Implicit TLS | Sending — preferred |
| SMTP | 587 | STARTTLS | Sending — the submission standard |
Mailbind itself will only connect on those four, and refuses private, loopback and link-local addresses, so a mail server field cannot be turned into a network scanner.
When the settings are not enough
Correct settings and a correct password still fail at several providers, because the password a client needs is not the one you sign in with. Apple and Yahoo require an app-specific password. Google requires one when two-step verification is on and you are not using OAuth. Infomaniak calls it a device password. Zoho needs one when two-factor authentication is on, and also needs IMAP switched on per address. Outlook.com has IMAP off by default and wants modern authentication.
Hosting providers are the other family: at IONOS, OVHcloud, Gandi and o2switch the mailbox has a password of its own, set in the control panel, and the control-panel login is not it. The eleven Connect pages on this site spell out which applies to which, with the provider’s own documentation linked.
Common questions
Is this reading my mail?
No. It makes a DNS query for the domain’s MX records. It never touches a mailbox, and it never asks for a password.
Why does it say “guess”?
Because no provider was recognised from the DNS records, so the names shown are the usual convention for a domain rather than something the records confirmed.
Do you keep the domain I typed?
No. It is used for the lookup and forgotten. Only a count of how often the tool was used is kept, with no addresses in it.
Do I need an account?
No. Every tool here works without signing in, and none of them asks for your mailbox password — they work on a domain name or on text you paste.
Keep reading
Or let Mailbind fill it in for you
The connect screen runs this detection as you type the address, and tests both servers before saving.
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Page updated October 29, 2026