booking.com
Live email deliverability and anti-spoofing audit, read from public DNS. Generated 2026-07-29 06:36 UTC — this page is cached for up to 6 hours, so re-check after changing a record.
96/100 — This domain is configured correctly for both sending and receiving. Accepts mail · Protected against spoofing · Hosted by Proofpoint
Findings
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mta sts
No MTA-STS policy, so inbound mail can be downgraded to an unencrypted connection.
Fix: Publish _mta-sts.booking.com and host a policy at https://mta-sts.booking.com/.well-known/mta-sts.txt.
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mx
Mail is handled by Proofpoint.
10 mxa-0032a201.gslb.pphosted.com, 10 mxb-0032a201.gslb.pphosted.com
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spf
SPF is published and enforcing.
v=spf1 include:%{ir}.%{v}.%{d}.spf.has.pphosted.com -all -
dmarc
DMARC is enforcing with p=reject.
v=DMARC1; p=reject; rua=mailto:dmarc_rua@emaildefense.proofpoint.com,mailto:booking@dmarc.postmastery.eu; ruf=mailto:dmarc_ruf@emaildefense.proofpoint.com
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dkim
DKIM keys found for 4 selectors.
s1._domainkey, s2._domainkey, mandrill._domainkey, hs1._domainkey
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bimi
BIMI is published; supporting clients can show your logo.
v=BIMI1; l=https://r.bstatic.com/static/img/newsletters/booking_bimi_icon_300.svg; a=https://q-xx.bstatic.com/data/mm/booking_com_20250711.pem;
Records
| MX | 10 mxa-0032a201.gslb.pphosted.com10 mxb-0032a201.gslb.pphosted.com |
|---|---|
| SPF | v=spf1 include:%{ir}.%{v}.%{d}.spf.has.pphosted.com -all |
| DMARC | v=DMARC1; p=reject; rua=mailto:dmarc_rua@emaildefense.proofpoint.com,mailto:booking@dmarc.postmastery.eu; ruf=mailto:dmarc_ruf@emaildefense.proofpoint.com |
| DKIM selectors | s1, s2, mandrill, hs1 |
| MTA-STS | not published |
| TLS-RPT | not published |
| BIMI | published |
| DNSSEC | not validating |
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