Postmaster+
Deliverability Monitoring

Complete Sender Compliance & Reputation

Your emails reach the inbox only when your sender infrastructure is healthy. Postmaster+ monitors every signal that affects deliverability — reputation scores, DNS authentication, spam complaints, and blocklist status — across all major mailbox providers in a single dashboard.

What We Monitor

Mailbox Provider Reputation Data

Postmaster+ aggregates reputation data from Gmail Postmaster Tools, Microsoft SNDS (Outlook/Hotmail), Yahoo, and Comcast into a unified dashboard. Instead of logging into four separate portals and manually checking each one, you see all your domain and IP reputation scores in one place with historical trending.

Gmail Postmaster Tools integration
Microsoft SNDS (Outlook/Hotmail)
Yahoo reputation monitoring
Comcast deliverability data
Historical trend analysis
Multi-domain support

DNS & Authentication Monitoring

Misconfigured authentication is the #1 preventable cause of deliverability problems. Postmaster+ continuously monitors your SPF, DKIM, DMARC, TLS, and IP reverse DNS records. When something breaks — a new sending IP missing from SPF, an expired DKIM key, a DMARC policy change — you'll know immediately.

SPF
All sending IPs authorized PASS
DKIM
Key valid, 2048-bit RSA PASS
DMARC
p=quarantine, rua configured PASS
TLS
TLS 1.3, valid certificate PASS
rDNS
PTR matches HELO domain PASS

Complaint Rate Monitoring

Google requires complaint rates below 0.3% to maintain good standing. Microsoft and Yahoo have similar thresholds. Postmaster+ tracks your spam complaint rate across providers with customizable alert thresholds, so you can catch a spike before it damages your reputation.

Current Rate

0.02%

Well below threshold

Warning

0.10%

Alert triggered

Danger

0.30%

Google threshold

Domain & IP Blocklist Monitoring

Not all blocklists matter. Postmaster+ monitors only the blocklists that actually affect email delivery — Spamhaus, Barracuda, SORBS, and other lists that mailbox providers actively query. No noise from irrelevant hobby lists that create false alarms.

Spamhaus (SBL, XBL, PBL, DBL)
Barracuda Reputation
SORBS
SpamCop
URIBL / SURBL
Continuous monitoring with alerts

Instant Alerts When Things Change

Deliverability issues cost money for every hour they go undetected. Postmaster+ sends alerts the moment something changes — a DNS record breaks, your complaint rate spikes, or your IP lands on a blocklist.

Email Alerts

Instant notification to your team when a monitored metric crosses your configured threshold.

Trend Detection

Spot gradual reputation decline before it becomes a crisis with historical trending and trendline analysis.

Custom Thresholds

Set alert levels that match your sending patterns. High-volume senders need tighter thresholds than occasional mailers.

Who Needs Deliverability Monitoring?

Email marketers & senders

If you send marketing, transactional, or lifecycle emails, your reputation directly impacts whether those emails reach the inbox. Monitoring catches problems before they snowball.

Deliverability teams

Replace manual checks across Gmail Postmaster Tools, SNDS, and blocklist lookup sites with a single automated dashboard. Focus on fixing issues, not finding them.

Email service providers (ESPs)

Monitor customer sending domains and IPs across your platform. Identify problematic senders before they affect shared infrastructure.

IT & security teams

Ensure email authentication (SPF, DKIM, DMARC) stays correctly configured as infrastructure changes. Catch misconfigurations immediately.

Ready to Maximize Your
Email Deliverability?

Join thousands of senders who trust Postmaster+ to protect their reputation and reach the inbox. Start free today.

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