Learning center
Guides for people who run email infrastructure
Cold email, deliverability, DNS and the tools behind them — practical, specific, no fluff.
Why Are My Emails Going to Spam? 9 Causes and Fixes
A diagnostic checklist for emails landing in spam: authentication, reputation, list quality, content and sending patterns — with free tools to check each one.
How Many Domains Do You Need for 1,000 Mailboxes?
Planning domains, mailboxes and costs for a 1,000-mailbox cold email operation — ratios, naming, providers and how to keep it manageable.
How Many Cold Emails Can You Send Per Day?
Realistic per-mailbox and per-domain cold email limits, why provider limits are the wrong number to aim for, and how to plan volume for your team.
How to Configure SPF, DKIM and DMARC (Step-by-Step)
A practical walkthrough for setting up SPF, DKIM and DMARC on a sending domain, with exact records for Google Workspace and Microsoft 365 and the mistakes that break them.