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Deliverability

Deliverability guides and product notes — no filler.

IONOS DNS editor adding a TXT record, showing the host-name conventions: @ for the root SPF record, _dmarc for DMARC, and selector._domainkey for DKIM.
DeliverabilityMay 20, 2026

How to set up SPF, DKIM, and DMARC in IONOS

Set up SPF, DKIM, and DMARC in IONOS: where the DNS editor is and what to enter in the host field for the root, _dmarc, and DKIM selector.

Porkbun DNS record editor adding a TXT record, with Type, Host, and Answer fields and an SPF, DKIM, DMARC legend showing each record's host name.
DeliverabilityMay 19, 2026

How to set up SPF, DKIM, and DMARC in Porkbun

Add SPF, DKIM, and DMARC records in Porkbun's DNS editor. Exactly what goes in the Host and Answer fields for each TXT record, in the right order.

SPF, DKIM, and DMARC each passing a check, marking a domain authenticated
DeliverabilityMay 13, 2026

SPF, DKIM, and DMARC explained

SPF, DKIM, and DMARC are the DNS records that prove your mail is really yours — and mandatory for bulk senders since 2024. What each does, explained.

An email routed to the inbox rather than the spam folder
DeliverabilityApril 28, 2026

How to improve email deliverability

How to improve email deliverability: the seven levers that decide inbox vs spam — authentication, list hygiene, engagement, reputation, warmup, and more.

A verification list where every row reads deliverable, with one row secretly flagged as a spam trap
DeliverabilityApril 7, 2026

What are spam traps, and what can verification do about them?

Spam traps punish poor list hygiene, and no verifier can reliably detect one. The three trap types, why detection fails, and what actually protects you.

A verification probe deferred with a 451 response, retried after five minutes, then accepted
DeliverabilityFebruary 24, 2026

What is greylisting? Why honest verifiers say unknown

Greylisting makes mail servers say "try again later" to unfamiliar senders. What that does to email verification, and why honest tools return unknown.

A bar chart of email bounce rates by industry, most clustered near a dashed 2.3% average line with a few rising well above it
DeliverabilityFebruary 11, 2026

Email bounce rate benchmarks: what's normal and what's not

The average email bounce rate is 2.33%, but normal varies by industry. Benchmarks by sector, how to calculate yours, and the fixes that actually lower it.

A bar chart of bounce rate climbing past a dashed 2% warning threshold
DeliverabilityJanuary 22, 2026

Why bounce rate is the metric mailbox providers actually watch

Hard bounces are the loudest reputation signal you send. Here's how providers read them, and the thresholds to stay under.