Guides on Gmail tabs (Primary, Promotions, Updates), Outlook Focused Inbox, inbox placement testing tools, seedlist methodologies, and spam-folder diagnostics. Everything you need to land in the actual inbox, not the spam fold.
Inbox Placement
Why Your Emails Land in Spam: 12 Most Common Reasons (2026)
Your emails are going to spam for one of 12 reasons: authentication, reputation, complaints, list hygiene, sending patterns, content, unsubscribe, engagement, identity, domain age, suspicious links, ...
Inbox Placement Testing Tools Compared (2026): GlockApps, MailReach, Mail Tester, Email on Acid
GlockApps, MailReach, Mail Tester and Email on Acid each test inbox placement differently. This guide compares methodology, provider coverage, and use case, separates seedlist testing from content ...
Outlook Focused Inbox: How It Works and How to Land There (2026)
Outlook Focused Inbox splits mail into Focused (priority) and Other (everything else). This guide covers how the classifier works, the signals that push mail one way or the other, Microsoft 365 ...
Gmail Tabs Explained: Primary vs Promotions vs Updates (2026)
Gmail sorts inbound mail into 5 tabs: Primary, Promotions, Social, Updates, and Forums. This guide explains how the classifier works, the signals that push mail one way or the other, how to land in ...
Inbox Placement Rate: What It Is and How It’s Measured (2026)
Inbox placement rate measures what share of your accepted mail actually lands in the primary inbox, not spam, promotions, or quarantine. This guide covers the difference with delivery rate, the four ...
