Cold Email DNS & Deliverability Checker
Query live DNS records across Google & Cloudflare DNS-over-HTTPS. Detect SPF flaws, missing 2048-bit DKIM keys, DMARC policies, and Custom Tracking Domains before sending a single cold outreach email.
Why Cold Email DNS Authentication Dictates Inbox Placement
In 2024–2026, Google Workspace and Yahoo Mail enforce strict requirements on high-volume outbound senders. Here is what each DNS record does:
SPF (Sender Policy Framework)
SPF specifies which mail servers are permitted to send emails from your domain. For cold email, exceeding the 10-lookup RFC limit or leaving your record as +all will instantly trigger spam filters across corporate Microsoft 365 and Google inboxes.
DKIM (2048-Bit Cryptography)
DKIM attaches a digital signature to every cold email you send. Receiver servers decrypt this signature using the public key published in your DNS. 2048-bit keys are the gold standard—preventing email tampering, spoofing, and spam flags.
DMARC Policy Enforcement
DMARC ties SPF and DKIM together. Having a DMARC policy of at least p=quarantine or p=reject signals to spam filters that your domain is strictly managed and protected from malicious impersonation.
MX Records & Reply Routing
Many amateurs forget to configure MX records on secondary lookalike domains. If a receiver's mail server cannot find active MX records, it classifies the sender domain as a "burner" and sends your message straight to the junk folder.
Custom Tracking Domains (CTD)
When using sequencers like Instantly or Smartlead, tracking open and click rates with shared generic pixels pools your domain reputation with spam spammers. A Custom Tracking Domain (e.g. track.yourdomain.com) isolates your engagement score completely.