Google sender compliance

Google requirements for all senders to Gmail accounts

Mail sent to personal Gmail accounts must meet Google's baseline authentication, DNS, transport and message-quality requirements. A useful compliance check must test the actual sending path, not merely confirm that records exist.

Problem description

A sender needs to determine whether a domain and sending IP meet Google's baseline requirements before mail is throttled, rejected or sent to spam.

Google sender compliance
SPF or DKIM  UNKNOWN
PTR / FCrDNS UNKNOWN
TLS          UNKNOWN
DMARC        RECOMMENDED
Spam rate    UNKNOWN

Diagnostic specification: this page defines the evidence required by the expanded sender-compliance check. It remains outside search indexes until that check is available.

Google requirements and the evidence needed

Requirement	Evidence	Safe result
SPF or DKIM	Envelope domain and sender IP, or DKIM selector and signing domain.	PASS only from the actual path; a record alone is CONFIGURED.
PTR and forward DNS	Public sender IP resolved to PTR and back through A/AAAA.	PASS only when forward DNS contains the original IP.
TLS	Receiver-observed headers or a transport test.	UNKNOWN from DNS alone.
Message format	Representative complete headers and rejection evidence.	UNKNOWN when only a domain is supplied.
Spam rate	Google Postmaster Tools.	UNKNOWN without Postmaster evidence.
DMARC	Organizational-domain record and message alignment.	Recommended for all; required for bulk senders.

Inputs an extended check needs

The visible From domain and envelope MAIL FROM domain.
An explicit public sender IPv4 or IPv6 address.
The DKIM selector and signing domain, or representative headers.
The complete rejection text, sender volume and message type.

Interpret the evidence honestly

DNS can show that authentication records are configured. It cannot prove TLS use, message-level DKIM verification, spam rate, or inbox placement. Those results must remain UNKNOWN until the required evidence is available.

Frequently asked questions

Does every sender to Gmail need DMARC?

Google requires all senders to authenticate with SPF or DKIM. DMARC is an additional requirement for bulk senders, and Google recommends it for every sending domain.

Can DNS alone prove Google sender compliance?

No. DNS can verify published records and sending-IP reverse DNS, but actual authentication, TLS, message format, spam rate and delivery require message or Postmaster evidence.

What is a valid PTR result for a sending IP?

The IP must resolve to a hostname through PTR, and that hostname must resolve through A or AAAA back to the same IP.

Related email diagnostics

Gmail requirements for sending 5,000 or more messages per dayCheck Gmail bulk sender requirements for SPF, DKIM, DMARC alignment, PTR, TLS, spam rate and one-click unsubscribe using path-specific evidence. Gmail 550 5.7.26: This email has been blocked because the sender is unauthenticatedDiagnose Gmail 550 5.7.26 safely. Separate unauthenticated-mail, SPF hard-fail and DMARC-policy branches before changing email DNS.

Primary sources: Google Email sender guidelines, Google Email sender guidelines FAQ, Google Postmaster sender requirements FAQ.