Manual Fastmail DNS Configuration

host websites at {mydomain.com} from your Fastmail file storage

• CNAME {mydomain.com} web.fastmail.com

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

host websites at subdomains, including www.{mydomain.com} from your Fastmail file storage

• CNAME *.{mydomain.com} web.fastmail.com

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

log in to your account at mail.{mydomain.com}

• CNAME mail.{mydomain.com} mail.fastmail.com

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 you 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

SPF allows receivers to know you send your mail via Fastmail, and other server

• 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

April 2023