To authenticate mail from your domain on Google Workspace you publish four DNS records: an SPF TXT record naming Google as a sender, a DKIM key that Google generates for you in the Admin console, a DMARC policy, and Google's MX record for inbound mail. The values below are the stable ones; always confirm the exact steps against Google's current setup guide, because the Admin console layout changes.
SPF
Publish one TXT record at your domain's root (host @):
v=spf1 include:_spf.google.com ~all
include:_spf.google.com authorizes Google's sending servers. If you also send through another service — a marketing platform, a help desk — add its include: before the ~all, in the same single record. A domain may publish only one SPF record; a second v=spf1 record is a misconfiguration that causes a PermError. Check the result with the SPF checker.
DKIM
Google generates the key for you, so DKIM is a two-step job — create the key in the console, then publish it in DNS:
- In the Google Admin console, go to Apps → Google Workspace → Gmail → Authenticate email.
- Select your domain and Generate new record. Keep the default 2048-bit key and the
googleselector unless you have a reason to change them. - Google shows a TXT record. The host is
google._domainkeyand the value beginsv=DKIM1; k=rsa; p=…. Publish that TXT record in your DNS. A 2048-bit key is long, and some DNS panels split the value into quoted chunks automatically. - Return to the console and Start authentication. Google verifies the record and begins signing outgoing mail.
Confirm the published key with the DKIM checker using the selector google. A dkim=none result after you publish usually means signing has not been turned on yet in step 4, or DNS has not propagated.
DMARC
Once SPF and DKIM are in place, publish a DMARC policy as a TXT record at host _dmarc:
v=DMARC1; p=none; rua=mailto:dmarc@yourdomain.com
Start at p=none, which only monitors and sends you aggregate reports at the rua address. Read the reports until you are confident every legitimate source is aligned, then raise the policy to p=quarantine and finally p=reject. Moving straight to p=reject risks blocking a legitimate sender you did not know about. Read your current record with the DMARC checker.
MX
Google now uses a single MX record. At your domain's root, publish:
Host: @ Priority: 1 Value: smtp.google.com
Older Google Workspace setups used five ASPMX records; the single smtp.google.com record is the current recommendation and either will deliver. Check yours with the MX lookup. If you are moving from another provider, only change MX once mailboxes are ready on Google, because MX controls where all inbound mail goes.
Check your work
DNS changes can take up to a day to propagate. After you publish, run a check from the Relaymetry home page to read all four records at once and confirm SPF, DKIM, and DMARC pass. For the mechanics behind these records rather than the Google-specific steps, see email authentication explained, and to set the same records up at a different mailbox provider, start from the setup hub.