Learn · Mailbox provider rules

Gmail and Yahoo sender requirements, as a checklist

Gmail and Yahoo ask every sender for SPF or DKIM, valid forward and reverse DNS, a spam rate below 0.3% and standards-compliant messages. Bulk senders also need SPF and DKIM, DMARC, From alignment and one-click unsubscribe for marketing and subscribed mail.

Map each rule to tinyRelay Check your DNS records

SENDER CHECKLIST

Tap what you have

Gmail · Yahoo

0 of 8 in place

ALL SENDERS

SPF or DKIM Forward and reverse DNS Spam rate below 0.3%RFC 5322 format

BULK SENDERS, ON TOP

SPF, DKIM and DMARC From alignment One-click unsubscribe Unsubscribe in 2 days

tinyRelay: one DKIM CNAME signs your mail, and PUT /domain/dns/check validates DKIM and SPF.

Summarized from Google's and Yahoo's own sender pages. Sources at the end.

Interactive checklist

Each requirement, mapped to what tinyRelay gives you.

Tap a requirement to see what Google and Yahoo say, which tinyRelay feature helps, and what stays on your side.

SPF and DKIM DMARC From alignment Forward and reverse DNS TLS Spam rate One-click unsubscribe Honor unsubscribes Message format Bounces

GOOGLE SAYS

All senders: SPF or DKIM. Over 5,000 messages a day to Gmail accounts: SPF and DKIM.

YAHOO SAYS

All senders: SPF or DKIM at a minimum. Bulk senders: both SPF and DKIM.

TINYRELAY FEATURE

DKIM CNAME + DNS check

One CNAME, tec1._domainkey to tec1.dkim.tinyemail.com, signs your mail. PUT /domain/dns/check validates DKIM and SPF. On you: publishing the records.

GOOGLE SAYS

Over 5,000 a day: set up DMARC for your sending domain. The enforcement policy can be none.

YAHOO SAYS

Bulk senders: a valid DMARC policy of at least p=none, and DMARC must pass. A rua reporting address is strongly recommended.

TINYRELAY FEATURE

Free DMARC lookup

DMARC is a record on your domain, so it's yours to publish. Our free checker reads it alongside SPF and DKIM.

GOOGLE SAYS

Over 5,000 a day: for direct mail, the From domain must align with the SPF or the DKIM domain.

YAHOO SAYS

Bulk senders: From domain aligned with the SPF or DKIM domain. Relaxed alignment is acceptable.

TINYRELAY FEATURE

Selector on your domain

The DKIM selector lives at tec1._domainkey on your own sending domain. Send from domains set up with us, and confirm alignment for your setup at onboarding.

GOOGLE SAYS

All senders: sending domains or IPs need valid forward and reverse DNS (PTR) records.

YAHOO SAYS

All senders: a valid forward and reverse DNS record for your sending IPs.

TINYRELAY FEATURE

Ask our team

Mail sent through tinyRelay leaves from our sending infrastructure. Ask us about the reverse DNS of the IPs your mail uses.

GOOGLE SAYS

All senders: use a TLS connection for transmitting email.

YAHOO SAYS

Not listed in Yahoo's sender requirements.

TINYRELAY FEATURE

Ask our team

The API is called over HTTPS. SMTP connection and TLS details are shared at onboarding.

GOOGLE SAYS

Keep the spam rate in Postmaster Tools below 0.3%. Aim for under 0.10% and avoid ever reaching 0.30%.

YAHOO SAYS

Keep your spam rate below 0.3%. Yahoo calculates it on mail delivered to the inbox.

TINYRELAY FEATURE

SPAM webhook events

When an email is marked as spam, a signed SPAM event reaches your endpoint with your metadata, so you can stop mailing that person. On you: watching Postmaster Tools.

GOOGLE SAYS

Over 5,000 a day: marketing and subscribed messages support one-click unsubscribe, with a clearly visible link in the body. Send List-Unsubscribe-Post and List-Unsubscribe headers.

YAHOO SAYS

Bulk senders: a working list-unsubscribe header with one-click for marketing and subscribed messages. The POST method (RFC 8058) is highly recommended.

TINYRELAY FEATURE

One-click unsubscribe headers

Set List-Unsubscribe and List-Unsubscribe-Post in the API's headers field. Your URL must accept a POST. Without them, tinyRelay adds a default unsubscribe header.

GOOGLE SAYS

When someone uses one-click, you receive a POST request at your List-Unsubscribe URL. Act on it.

YAHOO SAYS

Bulk senders: honor unsubscribes within 2 days.

TINYRELAY FEATURE

UNSUBSCRIBE events

An UNSUBSCRIBE webhook arrives when a recipient clicks the unsubscribe link, and bounce category 90 marks an unsubscribe as final. On you: updating your list.

GOOGLE SAYS

Format messages to the Internet Message Format standard, RFC 5322. Don't impersonate Gmail From: headers.

YAHOO SAYS

Comply with RFC 5321 and RFC 5322.

TINYRELAY FEATURE

Fields in, message out

Over the API you send subject, body, sender and recipients, and the message is built for you. Over SMTP your mail library builds it.

GOOGLE SAYS

As an extra step, automatically unsubscribe recipients who have multiple bounced messages.

YAHOO SAYS

Send timely, relevant email to an active, engaged audience.

TINYRELAY FEATURE

19 bounce categories

Every BOUNCED event carries HARD_BOUNCED or SOFT_BOUNCED and one of 19 categories. Add hard bounces to your own suppression list.

Paraphrased from Google's and Yahoo's sender pages. These features help you meet the rules; they don't make a sender compliant on their own.

Who the Gmail and Yahoo rules cover

Both providers split senders in two. A short list of requirements applies to everyone who sends to their users. A longer list applies to bulk senders.

Google draws the bulk line at more than 5,000 messages a day to Gmail accounts. Yahoo's page refers to bulk senders without restating a number, so if you send at volume, plan to meet both lists. Yahoo also says its requirements are subject to change, so check its page and blog for updates.

Requirements for all senders

Requirement	Google	Yahoo
Authentication	GoogleRequired SPF or DKIM	YahooRequired SPF or DKIM at a minimum
Forward and reverse DNS	GoogleRequired Valid for sending domains or IPs	YahooRequired Valid for sending IPs
TLS	GoogleRequired Use a TLS connection	YahooNot listed
Spam rate	GoogleBelow 0.3% In Postmaster Tools	YahooBelow 0.3%
Message standards	GoogleRFC 5322	YahooRFC 5321 and RFC 5322

Gmail and Yahoo bulk sender requirements

Requirement	Google (over 5,000 a day)	Yahoo (bulk)
Authentication	Google (over 5,000 a day)Both SPF and DKIM	Yahoo (bulk)Both SPF and DKIM
DMARC	Google (over 5,000 a day)Required Policy can be none	Yahoo (bulk)Required At least p=none, and it must pass; rua strongly recommended
Alignment	Google (over 5,000 a day)Required From domain aligned with SPF or DKIM domain	Yahoo (bulk)Required Same; relaxed alignment is acceptable
Unsubscribe	Google (over 5,000 a day)One-click For marketing and subscribed messages, plus a visible link	Yahoo (bulk)One-click List-unsubscribe header for marketing and subscribed messages, plus a visible link
Processing unsubscribes	Google (over 5,000 a day)Via POST One-click arrives as a POST to your List-Unsubscribe URL	Yahoo (bulk)Within 2 days
Spam rate	Google (over 5,000 a day)Below 0.30% Aim for under 0.10%	Yahoo (bulk)Below 0.3%

Google also says not to impersonate Gmail From: headers. Yahoo recommends a DKIM key of at least 1024 bits and ARC for mail you forward.

Do the rules apply to transactional email?

Most of them, yes. Authentication, forward and reverse DNS, spam rate and message standards apply to every message you send, including password resets and receipts. Both providers state the one-click unsubscribe requirement for marketing and subscribed messages. If you're unsure which lane an email is in, see transactional vs marketing email.

All mail

Transactional included

Authentication, forward and reverse DNS, spam rate and message standards.

Marketing and subscribed

One-click unsubscribe

As both providers state it, with a clearly visible link in the body.

One-click unsubscribe, briefly

RFC 8058 adds one header to the older List-Unsubscribe header. The message carries an HTTPS URL in List-Unsubscribe and the exact value List-Unsubscribe=One-Click in List-Unsubscribe-Post. The mailbox provider then sends a POST to that URL when someone unsubscribes. The RFC also asks for a valid DKIM signature covering both headers, and says the URL must not answer with a redirect.

headers field · RFC 8058Copy

"headers": {
  "List-Unsubscribe": "<https://acme.com/unsubscribe/…>",
  "List-Unsubscribe-Post": "List-Unsubscribe=One-Click"
}

Example URL · illustrative. Your URL must accept a POST.

With tinyRelay you set both headers in the API request's headers field. Header names are case-sensitive. The step-by-step is in the one-click unsubscribe guide, and the field reference is in the Send Email docs.

Where tinyRelay helps, and where it doesn't

No sending service makes you compliant on its own. Your domain, your content and who you send to decide that. tinyRelay gives you building blocks and tells you what happened to every message.

Authentication: DKIM signing with one CNAME, and PUT /domain/dns/check to validate DKIM and SPF. See SPF, DKIM and DMARC explained.
Feedback: SPAM, UNSUBSCRIBE and BOUNCED events arrive as signed webhooks, with your metadata.
Bounces: 19 documented bounce categories tell your app whether to retry, investigate or stop.
Ask our team: reverse DNS of sending IPs and SMTP TLS details.

Sources

Google, Email sender guidelines: support.google.com/a/answer/81126
Yahoo Sender Hub, Sender Best Practices: senders.yahooinc.com/best-practices
RFC 8058, Signaling One-Click Functionality for List Email Headers: datatracker.ietf.org/doc/html/rfc8058
RFC 5322, Internet Message Format: datatracker.ietf.org/doc/html/rfc5322
RFC 5321, Simple Mail Transfer Protocol: datatracker.ietf.org/doc/html/rfc5321

FAQ

Sender requirements, answered

What are the Gmail sender requirements?

All senders need SPF or DKIM, valid forward and reverse DNS, a TLS connection, a spam rate below 0.3% in Postmaster Tools and RFC 5322 formatting. Senders of more than 5,000 messages a day to Gmail accounts also need SPF and DKIM, DMARC, From alignment and one-click unsubscribe for marketing and subscribed messages.

What are Yahoo's sender requirements?

All senders need SPF or DKIM, a spam rate below 0.3%, valid forward and reverse DNS for sending IPs and compliance with RFC 5321 and 5322. Bulk senders also need SPF and DKIM, a DMARC policy of at least p=none, From alignment and one-click unsubscribe for marketing and subscribed messages, and must honor unsubscribes within 2 days.

Does one-click unsubscribe apply to password resets and receipts?

Google and Yahoo both state the one-click requirement for marketing and subscribed messages. Authentication, DNS and spam-rate requirements apply to all mail. Check the current guidelines for your case.

Does tinyRelay make my email compliant?

No sending service can do that on its own. tinyRelay gives you building blocks, such as DKIM signing with one CNAME, a DNS check endpoint, one-click unsubscribe headers and SPAM, UNSUBSCRIBE and BOUNCED events. Your domain, content and recipients decide the rest.

How do I check my SPF, DKIM and DMARC records?

Use the free SPF, DKIM and DMARC checker, which looks up your public DNS records, or call PUT /domain/dns/check to validate DKIM and SPF for a domain.

Get started

Send transactional email with a service that reports back.

SMTP relay or REST API, standalone or alongside tinyEmail. Tell us what you send and our team sets you up.

Get started Request pricing