fastmail.com
Live email deliverability and anti-spoofing audit. Every value below was read from public DNS at the moment this page was generated.
73/100 — Workable, but mail from this domain is more likely to land in spam than it needs to be. Accepts mail · Spoofable: anyone can forge this sender · Hosted by Fastmail
Findings
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spf
SPF ends in ~all (softfail); unauthorised mail is marked rather than rejected.
v=spf1 include:spf.messagingengine.com ~all
Fix: Move to -all once you have confirmed all senders are listed.
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dmarc
DMARC is in monitoring mode (p=none), so spoofed mail is still delivered.
v=DMARC1; p=none; rua=mailto:e3936a44@inbox.ondmarc.com
Fix: Move to p=quarantine and then p=reject once your reports show only legitimate senders failing.
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dkim
No DKIM key found at any common selector. Either DKIM is not configured, or it uses a custom selector we cannot discover from DNS alone.
Fix: Enable DKIM signing at your mail provider and publish the selector they give you.
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mx
Mail is handled by Fastmail.
10 in1-smtp.messagingengine.com, 20 in2-smtp.messagingengine.com
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mta sts
MTA-STS is published, so senders will refuse to downgrade to plaintext SMTP.
v=STSv1; id=20251216T132000
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tls rpt
TLS reporting is enabled.
v=TLSRPTv1; rua=mailto:e3936a44@inbox.ondmarc.com
Records
| MX | 10 in1-smtp.messagingengine.com20 in2-smtp.messagingengine.com |
|---|---|
| SPF | v=spf1 include:spf.messagingengine.com ~all |
| DMARC | v=DMARC1; p=none; rua=mailto:e3936a44@inbox.ondmarc.com |
| DKIM selectors | none discovered |
| MTA-STS | published |
| TLS-RPT | published |
| BIMI | not published |
| DNSSEC | not validating |
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