Pre-send compliance

Provider Policy Simulator

Score a sending profile against major mailbox-provider requirements before a campaign goes out.

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Simulate sender-policy readinessModels published provider requirements from the evidence you select. It does not predict inbox placement.

What this analysis does

Model authentication, alignment, unsubscribe, TLS and sending-pattern inputs against maintained provider policy profiles, with separate findings for major mailbox ecosystems.

How to use the result

Use real evidence

Paste the exact domain, header, message or configuration. The result is only as useful as the evidence supplied.

Review the findings

Mailybox separates observations from inferred causes so you can see what is known and what still needs verification.

Retest after changes

Email authentication and routing are stateful. Re-run the analysis after publishing a fix.

Interpretation matters

Email systems combine DNS, message-level evidence, provider policy and intermediate infrastructure. A single passing check is not proof that every message will deliver, and a single warning is not proof that a domain is misconfigured. Mailybox is designed to expose the evidence and the relationship between signals so the next action is clear.

Primary references