Deliverability Diagnostic

5-Layer Spam Email Audit Tool

Diagnose why your emails land in subscriber spam folder and suffer from low inbox placement rate. Evaluate your email campaign deliverability health layer-by-layer, from DNS records to list quality and generate a customized remediation checklist.

Layer 1: Authentication

Technical foundation for sending security and verification.

SPF (Sender Policy Framework) Authorizes sending IPs

DKIM (DomainKeys Identified Mail) Cryptographic verification

DMARC Policy Enforcement Alignment instructions for inbox filters

Custom Tracking Domain Link Alignment Eliminates shared ESP link risks

Authentication makes you eligible. It does not guarantee inbox placement.

Layer 2: Reputation

Trust signals determining how mailbox providers filter your mail.

Google Postmaster Domain Reputation Google inbox trust metric

Microsoft SNDS (Smart Network Data Services) Outlook / Hotmail deliverability data

IP & Domain Blacklist Status Listed on major spam databases

Domain Health & DNS Misconfigurations MX records, reverse DNS, checkups

Weak reputation can mean emails are accepted but filtered away from the inbox.

Layer 3: Placement

Delivered is not the same as visible. Verify where your email lands.

Verification & Seed List Testing How you measure inbox landing

Placement Performance (Average) Where emails land during tests

The real question: did the subscriber have a fair chance to see the email?

Layer 4: Sending Behavior

Patterns are watched. Aggressive volumes trigger security filters.

IP Address Reputation Strategy Dedicated vs. shared IP pools

Sending Domain & Subdomain Segmentation Transactional vs. Marketing isolation

IP & Domain Warming Schedule Gradually building volume on new infrastructure

List-Unsubscribe Header & ISP Feedback Loops (FBL) Simplifies opt-outs & registers complaint data

High volume sending requires rigorous domain segmentation and feedback loop registration.

Layer 5: Data Quality

Bad list data creates negative signals that trigger filters.

List Cleaning & Verification Frequency Removing bad/non-existent addresses

Average Hard Bounce Rate Invalid address bounces

Sunset Policy for Inactive Subscribers Pruning users who do not engage

Spam Complaint Rate Subscribers marking messages as spam

Bad data doesn’t only reduce inbox placement. It damages reputation.

0 / 100 Trust Score

Critical Risk

Audit Breakdown

1. Authentication 0%

2. Reputation 0%

3. Placement 0%

4. Sending Behavior 0%

5. Data Quality 0%

Plan

Remediation Roadmap

Priority tasks dynamically updated based on your audit results. Resolve these in sequence to move your campaigns out of spam folders.

High Priority (0)

Medium Priority (0)

Optimization (0)

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