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DNS checker for cold email senders.
Audit your sending domain's SPF, DKIM, DMARC, and MX records in seconds. With operational notes on every failure mode — not just pass/fail.
What this checks. The four DNS records that determine whether a cold email lands in primary, promotions, or spam: SPF (RFC 7208), DKIM (RFC 6376), DMARC (RFC 7489), and MX. The output includes the raw record values plus operational notes on common failure modes — the 10-lookup limit, the p=none monitoring trap, missing aggregate reporting, weak key sizes.
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