EMAIL DELIVERABILITY // THE FUNDAMENTALS
Email Deliverability: What Decides Where Your Email Lands
Your ESP reports 99% delivered, and yet opens keep sliding, because "delivered" includes the spam folder. Email deliverability is the discipline of getting mail into the inbox itself, and it can be measured, monitored, and improved factor by factor.
Inbox placement
67%
··%
· ·
Authentication
checking 130+ blacklists
Sample data. Seed results are estimates, not guarantees.
What is a email deliverability?
Email deliverability is the ability of your email to reach the inbox rather than the spam folder or the Promotions tab. It is not the same as delivery: a 99% delivery rate only means servers accepted the mail, not that a human will see it. Deliverability is decided by five factor groups: authentication (SPF, DKIM, DMARC), sender reputation on your domain and IPs, content and structure, sending infrastructure, and recipient engagement. Inboxes measures each one. Placement tests across 27+ seed mailboxes at 6 providers show where mail actually lands; continuous monitoring tracks reputation, 130+ blacklists, and parsed DMARC reports; and every test returns fixes ranked by impact, so you work on the factor actually costing you the inbox. Two things stay true regardless of tooling: seed panels are directional estimates, and nobody can guarantee placement. Durable deliverability comes from authenticated mail people actually want.
What you get
Email deliverability, done properly
All five factors, one place
Authentication, reputation, content, infrastructure, and engagement signals live on one timeline instead of five tabs, so cause and effect stay connected.
Measured against real mailboxes
Placement is tested with live seed accounts at Gmail, Outlook, Yahoo, iCloud, GMX, and Zoho, not inferred from a content score or a self-reported delivery rate.
Monitoring, not snapshots
Deliverability decays quietly: a new blacklist listing, an expiring DKIM key, a reputation dip. Continuous checks catch the slide weeks before your open rate does.
Fixes ranked by impact
A DMARC alignment failure outranks a subject-line tweak. Every report orders its actions so the first hour of work moves the most mail.
How it works
From send to fix list in four steps
Baseline your placement
Run an inbox placement test from your own ESP and see the current split of inbox, Promotions, and spam per provider.
Audit the foundations
The same pass validates SPF, DKIM, and DMARC from live headers and screens your IPs and domain against 130+ blacklists.
Turn on monitoring
Reputation trends, blacklist watch, and DMARC report parsing run continuously, with alerts when a factor moves.
Improve in order
Apply the ranked fixes, re-test after each change, and keep the board green send after send.
The honest boundary: seed results are directional estimates and nobody can guarantee inbox placement. Inboxes finds the fixable causes, tells you exactly what to change, and monitors the result. No warmup networks, no bot opens, ever. Full detail on the methodology page.