How the infrastructure health score works

Updated Apr 8, 2026 · 5 min read

The 0–100 score, what inputs it uses, how to improve it.

On this page · 3

What goes into the score
What drops a score
How to improve a score

The health score is 0–100 per domain and per mailbox, refreshed daily. It exists because operators need a single number to triage from - not 14 separate signals to correlate manually.

What goes into the score

DNS authentication validity - 40% weight. Includes SPF, DKIM, DMARC, MX status.

Blacklist status across 14 sources - 30% weight. Spamhaus SBL, DBL, SURBL, Barracuda, etc.

Seed placement test results - 30% weight. Daily test against a Workspace + M365 seed list.

What drops a score

DKIM key mismatch or rotation in progress - typically -8 points until resolved.

Any blacklist hit (Spamhaus SBL/DBL, SURBL, Barracuda) - -15 to -25 depending on the source.

Seed placement drop below 75% inbox - proportional to the gap; -15 at 50% placement.

Domain age under 30 days - -5 (recoverable; the domain ages out automatically).

How to improve a score

For DNS issues, click the offending row in the domain page and the dashboard shows the exact record problem and the proposed fix. Most DNS issues resolve in a single click - Inboxlee re-publishes the record.

For blacklist hits, the source determines the response. Spamhaus issues require investigating the underlying sending pattern (volume spike, list-quality issue, compromised credential) before delisting. We surface a remediation checklist on the alert.

For placement drops, pause sending for 48 hours, audit the most recent campaigns, and let reputation recover. Resume at half volume and ramp back up over a week.

Below 70 is the action threshold. Above 85 is healthy. Between 70–85 is a watch zone.

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