This automation builds an automated email bounce detection and list cleanup system using n8n, Gmail, Google Sheets, and Slack.It identifies failed email deliveries and updates contact status without manual review.The workflow fetches bounce notification emails directly from Gmail.Failed email addresses are extracted using deterministic parsing logic.Only recent bounce events are processed to avoid duplication.All contacts are read from Google Sheets as the source of truth.Bounce data is matched against the contact list accurately.Each contact is marked as invalid or inactive with timestamps.Daily statistics are calculated for bounced and untouched emails.A summary report is sent automatically to Slack.All updates remain auditable inside Google Sheets.The result is a clean, reliable, and continuously maintained email list.