How to Monitor Email Deliverability in Real Time

📬 Monitoring email deliverability in real time is essential for marketing teams aiming to optimize campaign performance and maintain their sender reputation.

Maintaining high email deliverability rates can be daunting without proper tools and insights. In this article, you’ll learn practical, step-by-step methods to build automated workflows that integrate popular services like Gmail, Google Sheets, Slack, and HubSpot using platforms such as n8n, Make, and Zapier.

By following this guide, startup CTOs, automation engineers, and operations specialists will gain technical expertise to track delivery metrics effectively, trigger alerts for issues, and scale their email infrastructure with confidence.

Why Real-Time Email Deliverability Monitoring Matters for Marketing

Email deliverability indicates the success of messages reaching subscribers’ inboxes. Poor deliverability leads to lost revenue, lower engagement, and potential blacklisting.

With real-time monitoring, marketing teams gain immediate visibility into delivery rates, bounces, spam reports, and engagement trends. Automations can swiftly detect and resolve problems, minimizing campaign damage and maximizing ROI.

Key benefits include:

• Rapid detection of delivery failures
• Proactive reputation management
• Automated reporting and alerts
• Data-driven campaign adjustments

Let’s dive into building automated workflows that solve these challenges using modern automation tools.

Overview of Automated Email Deliverability Monitoring Workflow

At a high level, the workflow includes:

1. Trigger: Email sending event or API webhook data about delivery status
2. Data capture: Extract key email metrics like bounce type, open rates, spam complaints
3. Data storage: Save the metrics into a centralized Google Sheet or CRM system
4. Condition evaluation: Detect issues like hard bounces, drop in open rates, or blacklist warnings
5. Alerts & actions: Notify teams via Slack, email, or update CRM records

Automation Platforms Comparison for Email Deliverability Monitoring

Tool	Pricing	Pros	Cons
n8n	Free self-host or paid cloud plans from $20/mo	Highly customizable; open source; extensive integrations	Requires initial setup; self-hosting needs maintenance
Make (formerly Integromat)	Free tier; paid plans start at $9/mo	Visual scenario builder; good for complex workflows	API limits in free plan; steeper learning curve
Zapier	Free for limited tasks; paid from $19.99/mo	User friendly; large app ecosystem	Limited customization; slower execution

Step-by-Step Guide: Building an Email Deliverability Monitoring Workflow with n8n

1. Define the Problem and Intended Benefits

Marketing teams sending bulk campaigns often lack immediate visibility on email delivery issues, leading to delayed responses to bounces or spam complaints. This workflow helps by:

• Automatically capturing delivery events
• Logging detailed metrics in a central repository
• Alerting teams about critical issues for fast remediation

2. Tools and Services Required

• Gmail API: For sending emails and tracking basic metrics
• SendGrid or similar SMTP provider: For advanced bounce and complaint data
• Google Sheets: Central data storage and historical tracking
• Slack: Real-time team notifications
• n8n Automation Platform: Orchestrates data flows and logic

3. Workflow Architecture (Trigger → Transformations → Actions)

Trigger: Setup a webhook node in n8n to receive JSON payloads from SendGrid webhook about email events like delivered, bounced, opened, or reported spam.

Transformations: Extract event type, email address, timestamp, bounce reason, and user engagement data.

Actions: Append data to Google Sheets rows; evaluate bounce severity; alert via Slack if hard bounce or spam report occurs.

4. Node-by-Node Breakdown

1. Webhook Node:
   Configure n8n webhook to accept POST requests from SendGrid.
   Path: /email-events
   HTTP Method: POST
2. Function Node – Parse Data:
   Transform raw webhook JSON to extract:
   • event: delivered, bounce, spamreport, open, etc.
   • email: recipient’s email address
   • timestamp: event time
   • bounce_type and reason (if applicable)
3. Google Sheets Node – Append Row:
   Add a row with extracted data to a spreadsheet named “Email Deliverability Logs”.
   Fields: Email, Event Type, Timestamp, Bounce Reason
4. If Node – Condition Check:
   Evaluate if event === ‘bounce’ && bounce_type === ‘hard’ or event === ‘spamreport’
   Proceed to alert node if true
5. Slack Node – Send Message:
   Post alert message to marketing channel
   Message Example: “Alert: Hard bounce detected on {{email}} at {{timestamp}} due to {{bounce_reason}}.”

5. Sample n8n Function Code Snippet (Parsing Webhook) 🛠️

return items.map(item => {
  const event = item.json.event;
  const email = item.json.email;
  const timestamp = item.json.timestamp;
  const bounce_type = item.json['bounce_type'] || null;
  const bounce_reason = item.json['reason'] || null;

  return {
    json: { event, email, timestamp, bounce_type, bounce_reason }
  };
});

6. Error Handling and Robustness Tips

• Retries: Configure automatic retries on webhook failures (e.g., 3 attempts with exponential backoff)
• Idempotency: Use unique event IDs to avoid duplicate processing by checking Google Sheets or a cache
• Logging: Log failed runs and error responses in n8n for audit trail
• Rate Limits: Respect API rate limits for Google Sheets and Slack; implement queueing if necessary

7. Security Considerations 🔒

• Use OAuth2 or API keys with least privileges for Gmail, Google Sheets, and Slack integrations
• Sanitize all incoming webhook data to avoid injection attacks
• Mask or tokenize personal identifiable information (PII) where possible
• Limit access to the workflow and logs to authorized personnel

8. Scaling and Performance

To handle higher email volumes:

• Switch from polling to webhook triggers for instant data
• Implement queues or batch appends to Google Sheets
• Use concurrency settings in n8n to process multiple events simultaneously
• Modularize workflow by separating parsing, storage, and alerts into sub-workflows for maintainability
• Utilize version control for workflow changes to track updates

9. Testing and Monitoring Tips

• Create sandbox environments with test email events to validate workflow logic
• Review run history and output logs regularly
• Set up proactive Slack alerts for workflow failures
• Use webhook request logging tools to debug incoming payloads

Alternative Workflow Example: Using Zapier with HubSpot and Gmail

Zapier can simplify integration for teams preferring no-code tools:

1. Trigger: New delivery event from SMTP provider via webhook or direct Zapier integration
2. Action: Update HubSpot contact timeline with email status
3. Filter: Check if bounce or spam report occurred
4. Action: Send Slack notification to marketing channel
5. Logging: Add row to Google Sheets for record keeping

This approach suits smaller teams, though with less customization and slower reaction times compared to n8n or Make workflows.

Comparison: Webhook vs Polling for Email Deliverability Data

Method	Latency	Resource Usage	Reliability	Implementation Complexity
Webhook	Near real-time (seconds)	Low	High (if retried on failure)	Moderate (needs exposure of endpoint)
Polling	Delayed (minutes to hours)	High (frequent requests)	Medium	Low (simpler to implement)

Comparison: Google Sheets vs CRM Databases for Deliverability Logs

Storage Type	Scalability	Complex Query Support	Integration Complexity	Cost
Google Sheets	Limited (max 10,000 rows effectively)	Basic (filter/sort only)	Low	Free or minimal
CRM Database (e.g., HubSpot)	High (dedicated infrastructure)	Advanced (custom queries)	Medium	Variable (subscription-based)

Frequently Asked Questions

Conclusion

Monitoring email deliverability in real time empowers marketing teams to act swiftly on delivery issues, maintain sender reputation, and improve campaign success rates. By leveraging automation platforms like n8n, Make, or Zapier integrated with Gmail, Google Sheets, Slack, and HubSpot, you can build scalable, robust workflows tailored to your organization’s needs.

Start by identifying key email events to track, set up webhook triggers, build transformation logic, and automate notifications and reporting. Prioritize error handling and security to ensure reliable operations.

Take action today: Implement your first automated email deliverability workflow and watch your marketing engagement soar. For tailored guidance or advanced implementations, contact automation experts or explore community resources to scale your solution effectively!