The inbox is earned, not guaranteed
Email deliverability is the discipline of ensuring your messages reach the recipient's inbox rather than their spam folder or getting blocked entirely. Here's how it works — and how SendOut automates it.
What determines your deliverability score?
Authentication (SPF/DKIM/DMARC)
35%Sender reputation
30%Sending behaviour
20%Content & engagement
15%Authentication
SPF, DKIM, and DMARC are the technical foundation of inbox delivery. Without them, ESPs treat your email as suspicious — even if the content is clean.
Declares which servers can send on your domain's behalf
Cryptographic signature that proves the message wasn't tampered
Instructs ESPs what to do when SPF/DKIM checks fail
Shows your brand logo in supported inboxes
Reputation
Sender reputation is a score ESPs assign to your IP and domain based on engagement, complaint rates, and bounce history. It's earned slowly and lost quickly.
Opens and replies signal your emails are wanted
Spam reports above 0.1% trigger filtering
Hard bounces above 2% damage domain reputation
Presence on major blacklists blocks delivery entirely
Sending Behaviour
How you send matters as much as what you send. Sudden volume spikes, identical templates, and low-engagement lists all trigger spam filters before a human ever reads your email.
New domains must ramp volume gradually over weeks
Regular cadence beats irregular bursts
Remove bounces and inactives before each campaign
Avoid spam trigger words, excessive links, or images
The #1 mistake cold emailers make
Sending high-volume campaigns from freshly registered domains with no warm-up history. Email service providers assign new domains a neutral reputation — one that turns negative the moment they see a burst of outbound mail with low engagement. A domain blacklisted in the first 30 days can take months to recover, if it ever does.
How SendOut automates all of this
You focus on writing good emails. SendOut handles the infrastructure that makes sure they land.
Validates your authentication
Checks SPF, DKIM, and DMARC on every connected domain and alerts you instantly if a record goes missing or breaks.
Monitors 120+ blacklists
Automated checks every 6 hours against all major blacklist providers. Get notified before your campaigns are affected.
Warms up new domains
Human-like warm-up sequences build sending reputation from scratch — the right way, not shortcuts that get you banned.
Shows you inbox placement
Real-time visibility into whether your emails reach the inbox, promotions, or spam for each major provider.
Check your domain's deliverability health
Connect your mailboxes and get a full deliverability audit in seconds.
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