Email deliverability check
Check the four DNS records that decide whether your email reaches the inbox: MX, SPF, DKIM and DMARC — with a plain-English grade.
The four records that matter
MX — where mail arrives
Lists the servers that accept email for your domain, in priority order. No MX record means inbound mail bounces. Two or more records from the same provider is normal redundancy.
SPF — who may send as you
A TXT record listing the servers allowed to send email using your domain. Watch the ending: -all is a hard fail (strict, recommended once you are certain the list is complete), ~all is a soft fail (safe default), and ?all is neutral and enforces nothing. SPF is limited to ten DNS lookups — if you chain several include: statements you can exceed it, at which point SPF silently stops working.
DKIM — the cryptographic signature
Your mail server signs each message with a private key; receivers verify it against a public key published in DNS at a selector name. We probe the common selectors used by Google, Microsoft, Zoho and the major bulk senders. A negative result here does not always mean DKIM is missing — it may simply use a custom selector name we cannot guess.
DMARC — the policy
Ties SPF and DKIM together and tells receivers what to do with failures: p=none (monitor only), p=quarantine (send to spam) or p=reject (refuse outright). Most domains should progress none → quarantine → reject over a few weeks while reading the aggregate reports. Without DMARC, anyone can forge your domain in a phishing email and receiving servers have no instruction to stop them.
FAQ
I have SPF but mail still lands in spam
SPF alone is weak. Add DKIM and DMARC, make sure the sending IP has a matching reverse DNS record, and check whether that IP is on a blocklist.
Should I jump straight to p=reject?
No. Start at p=none, collect the aggregate reports for two to four weeks to find legitimate senders you had forgotten — invoicing tools, CRMs, mailing lists — then tighten.
You did not find my DKIM record
We test the common selector names. A custom selector will not be found by probing; check the DNS TXT record your provider gave you directly.
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