anthropic.com
Live email deliverability and anti-spoofing audit. Every value below was read from public DNS at the moment this page was generated.
91/100 — This domain is configured correctly for both sending and receiving. Accepts mail · Protected against spoofing · Hosted by Google Workspace
Findings
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spf
SPF ends in ~all (softfail); unauthorised mail is marked rather than rejected.
v=spf1 include:_spf.google.com ~all
Fix: Move to -all once you have confirmed all senders are listed.
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mta sts
No MTA-STS policy, so inbound mail can be downgraded to an unencrypted connection.
Fix: Publish _mta-sts.anthropic.com and host a policy at https://mta-sts.anthropic.com/.well-known/mta-sts.txt.
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mx
Mail is handled by Google Workspace.
1 aspmx.l.google.com, 5 alt1.aspmx.l.google.com, 5 alt2.aspmx.l.google.com, 10 alt3.aspmx.l.google.com, 10 alt4.aspmx.l.google.com
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dmarc
DMARC is enforcing with p=reject.
v=DMARC1; p=reject; sp=reject; rua=mailto:f0cef134490d4d43b9c134fc3c2a3481@dmarc-reports.cloudflare.net,mailto:dmarc-reports@anthropic.com; ruf=mailto:dmarc-reports@anthropic.com; fo=1
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dkim
DKIM keys found for 1 selector.
google._domainkey
Records
| MX | 1 aspmx.l.google.com5 alt1.aspmx.l.google.com5 alt2.aspmx.l.google.com10 alt3.aspmx.l.google.com10 alt4.aspmx.l.google.com |
|---|---|
| SPF | v=spf1 include:_spf.google.com ~all |
| DMARC | v=DMARC1; p=reject; sp=reject; rua=mailto:f0cef134490d4d43b9c134fc3c2a3481@dmarc-reports.cloudflare.net,mailto:dmarc-reports@anthropic.com; ruf=mailto:dmarc-reports@anthropic.com; fo=1 |
| DKIM selectors | google |
| MTA-STS | not published |
| TLS-RPT | not published |
| BIMI | not published |
| DNSSEC | not validating |
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