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The WordPress Email Authority

WordPress sends email from your domain, but receivers check your DNS records to decide whether to trust it. A missing SPF record gets you in spam. No DKIM means Gmail’s bulk sender rules can block you. A p=none DMARC policy is a compliance gap that will bite when you pass 5,000 messages per day.

This checker queries your records live using DNS-over-HTTPS — no installation, nothing sent to a server.

DNS Auth Checker

Enter your sending domain to check SPF, DKIM, DMARC, and MX — and see how you score against Gmail, Yahoo, and Microsoft 365 bulk-sender requirements.

What each record does

SPF (Sender Policy Framework) lists the mail servers authorised to send on behalf of your domain. When you use an SMTP service like SendGrid or Postmark, you add their include: directive to your SPF TXT record. A missing or incomplete SPF record is the most common cause of WordPress email landing in spam.

DKIM (DomainKeys Identified Mail) adds a cryptographic signature to every outbound message. The receiving server checks the signature against a public key in your DNS. DKIM survives email forwarding better than SPF — it’s the record Gmail checks when deciding whether to show the padlock icon.

DMARC (Domain-based Message Authentication) ties SPF and DKIM together and tells receivers what to do with mail that fails. A policy of p=none means monitoring only. p=quarantine puts failures in spam. p=reject blocks them outright. Gmail and Yahoo require at least p=quarantine for bulk senders.

MX records point incoming mail to the right server. The checker reads them as a sanity check — misconfigured MX records can cause bounce loops and explain why reply-to addresses never receive responses.

Compliance requirements

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