Manual DNS configuration

This page provides details on advanced domain setup options in Fastmail, and is meant for more technical users. DNS is a complicated system that can break your website and/or mail delivery, so we strongly suggest that you do not make any changes to your DNS unless you have an understanding of DNS, or are following explicit instructions.

Looking for basic domain information or setup instructions?

Want more general information about how DNS works?

Full list of DNS records

This is the full list of DNS records we can publish for you. You can choose to disable any of these. The information is also available on the Settings → Domains screen, in the Show DNS Settings section.

All entries have a 1 hour TTL.

Websites

  • Allows you to host websites at http://{mydomain.com} from your Fastmail file storage.
  • A {mydomain.com} 66.111.4.53
  • A {mydomain.com} 66.111.4.54

Standard Mail

  • Allows you to receive email at standard addresses, e.g. user@{mydomain.com}.
  • MX {mydomain.com} 10 in1-smtp.messagingengine.com
  • MX {mydomain.com} 20 in2-smtp.messagingengine.com

Subdomain Websites

  • Allows you to host websites at subdomains, including http://www.{mydomain.com}, from your Fastmail file storage.
  • A *.{mydomain.com} 66.111.4.53
  • A *.{mydomain.com} 66.111.4.54

Subdomain Mail

  • Allows you to receive email at subdomain addresses, e.g. foo@user.{mydomain.com}.
  • MX *.{mydomain.com} 10 in1-smtp.messagingengine.com
  • MX *.{mydomain.com} 20 in2-smtp.messagingengine.com

Webmail Login Portal

  • Allows you to log in to your account at http://mail.{mydomain.com}.
  • A mail.{mydomain.com} 66.111.4.147
  • A mail.{mydomain.com} 66.111.4.148

Allow mail at subdomains

  • An 'A' record hides the wildcard subdomain MX record. This overrides that to allow receiving email addressed to foo@mail.{mydomain.com}.
  • MX mail.{mydomain.com} 10 in1-smtp.messagingengine.com
  • MX mail.{mydomain.com} 20 in2-smtp.messagingengine.com

DKIM

  • Allows us to sign the mail you send so receivers can verify it's from you. This is important to ensure your message is not classified as spam. Note you'll need to add all three.
  • CNAME fm1._domainkey.{mydomain.com} fm1.{mydomain.com}.dkim.fmhosted.com
  • CNAME fm2._domainkey.{mydomain.com} fm2.{mydomain.com}.dkim.fmhosted.com
  • CNAME fm3._domainkey.{mydomain.com} fm3.{mydomain.com}.dkim.fmhosted.com
  • Deprecated, for old domains only:
    • CNAME mesmtp._domainkey.{mydomain.com} mesmtp.{mydomain.com}.dkim.fmhosted.com

SPF

  • Allows receivers to know you send your mail via Fastmail, and other servers.
  • TXT {mydomain.com} v=spf1 include:spf.messagingengine.com ?all

Client email auto-discovery

  • Allows email clients to automatically find the correct settings for your account.
  • SRV _submission._tcp.{mydomain.com} 0 1 587 smtp.fastmail.com
  • SRV _imap._tcp.{mydomain.com} 0 0 0 .
  • SRV _imaps._tcp.{mydomain.com} 0 1 993 imap.fastmail.com
  • SRV _pop3._tcp.{mydomain.com} 0 0 0 .
  • SRV _pop3s._tcp.{mydomain.com} 10 1 995 pop.fastmail.com
  • SRV _jmap._tcp.{mydomain.com} 0 1 443 api.fastmail.com

Client CardDAV auto-discovery

  • Allows CardDAV clients to automatically find the correct settings for your account.
  • SRV _carddav._tcp.{mydomain.com} 0 0 0 .
  • SRV _carddavs._tcp.{mydomain.com} 0 1 443 carddav.fastmail.com

Client CalDAV auto-discovery

  • Allows CalDAV clients to automatically find the correct settings for your account.
  • SRV _caldav._tcp.{mydomain.com} 0 0 0 .
  • SRV _caldavs._tcp.{mydomain.com} 0 1 443 caldav.fastmail.com
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