Mert Ozdemir

Head of Deliverability, Puzzle Inbox

Mert runs the deliverability practice at Puzzle Inbox. He has provisioned over 70,000 Google Workspace and Microsoft 365 cold email mailboxes and writes about what actually moves inbox placement.

Mert has been working in cold email infrastructure for the past nine years, first as a deliverability consultant for B2B SaaS companies and now as Head of Deliverability at Puzzle Inbox. He focuses on the operational side of cold email at scale: tenant architecture for Google Workspace and Microsoft 365, SPF / DKIM / DMARC alignment, warmup curves, complaint-rate triage, and the day-to-day failure modes that drag down reply rates. His writing on the Puzzle Inbox blog covers everything from the mechanics of pre-warmed inboxes to the practical sending caps for Gmail and Outlook in 2026.

Areas of expertise

  • Cold email deliverability
  • Google Workspace tenant architecture
  • Microsoft 365 cold email
  • SPF DKIM DMARC
  • Email warmup
  • Inbox placement testing

Recent articles by Mert

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