Email Deliverability and Email Checker
How a list checker and good sending practices work together to keep your emails in the inbox.
Deliverability is the share of your emails that reach the inbox rather than the spam folder or nowhere at all. Two things decide most of it: who you send to and how you send.
Who you send to
Providers watch hard bounces and spam complaints. An email checker keeps invalid, disposable and risky addresses off the list, which is the biggest lever on bounce rate.
How you send
- Authenticate your domain with SPF, DKIM and DMARC.
- Keep volume steady; sudden spikes look like abuse.
- Make unsubscribing easy so unhappy readers do not click "spam".
- Send content people expect and relevant segments only.
Where the checker fits
Run it before every large send and on every new import. It handles the list side so the rest of your effort goes into content and timing.
Signs of a deliverability problem
Falling open rates, rising bounces, messages missing from seed inboxes or delays at Gmail and Outlook. If you see them, clean the list first, then check authentication.
The three levers of deliverability
Inbox placement is decided by three things you control and one you do not:
- Identity: SPF, DKIM and DMARC prove the message really comes from your domain.
- Reputation: the history your domain and sending IP have with each mailbox provider, built from bounces, complaints and engagement.
- Content: what the message says and links to.
- Recipient behaviour is the part you do not control, which is why the first three have to be clean.
An email checker works on reputation. It removes the addresses that would generate hard bounces, the signal providers weigh most heavily.
A practical order of work
- Confirm SPF, DKIM and DMARC pass on a test message.
- Verify the list and remove invalid addresses.
- Send to your most engaged contacts first when you start again after a pause.
- Review bounces and complaints after every campaign and act on them within a day.
Typical numbers to aim for
Keep hard bounces under 2% and spam complaints well under 0.1%. These are common guidelines, not guarantees: mailbox providers publish few exact thresholds and change their systems.
One warning
A clean list does not rescue a message people do not want. If recipients never open or often report your mail, fix the relevance before you fix anything else.
