Mail domain report: protonmail.com

SPF

pass

SPF record published

Found

Record: v=spf1 include:_spf.protonmail.ch ~all
DNS lookups: 2 of 10
Void lookups: 0 of 2

Checks

✓ No deprecated ptr mechanism #1

No ptr mechanism found in SPF record.
✓ 2 of 10 DNS lookups #2

SPF record needs 2 DNS lookups (limit is 10).
✓ Ends with ~all #3

SPF record properly uses ~all to restrict unauthorized senders.
✓ Record published #6

SPF record exists for this domain.
✓ Single record #16

Exactly one SPF record is published.
✓ Valid syntax #25

All SPF mechanisms and modifiers are valid.
✓ No void lookups #26

All include/redirect targets exist.
✓ No overly broad IP ranges #27

All ip4/ip6 ranges are narrow enough.

DMARC

warn

p=quarantine (_dmarc.protonmail.com)

Found

Record: v=DMARC1; p=quarantine; fo=1; aspf=s; adkim=s;
Found at: _dmarc.protonmail.com

Tag	Value	Meaning
v	DMARC1	Version
p	quarantine	Policy
adkim	s	DKIM alignment (r = relaxed, s = strict)
aspf	s	SPF alignment (r = relaxed, s = strict)
fo	1	Failure reporting options

Checks

!

Policy: quarantine

DMARC policy is set to 'quarantine'. Consider upgrading to 'reject' for stronger protection once you've verified legitimate emails are passing authentication.

#4
✓ Record published #5

DMARC record exists for this domain.
✓ Valid syntax #17

DMARC record syntax is valid.
✓ Applies to 100% of mail #18

DMARC policy applies to all failing mail.
!

No aggregate reports (rua)

DMARC record has no rua tag, so you receive no aggregate reports about who sends mail as your domain. Add rua=mailto:...

#19
✓ Subdomain policy: quarantine #20

Subdomains are covered by policy 'quarantine'.

DKIM

warn

No keys found under the checked selectors

Found

Selectors: None found
_domainkey: NOERROR

Checks

!

No key under common selectors

The _domainkey name exists but no DKIM key was found under the common selectors. Selectors are provider-specific; check yours with -selector.

#7

DNSSEC

pass

Signed, DS published at parent

Found

DNSKEY records: Yes (2)
DS at parent: Yes
Algorithms: ECDSAP256SHA256 (13)
Key tags: 44693, 56075
Signatures valid until: 5 November 2026, 11:14 UTC

Checks

✓ Signed, DS published at parent #8

DNSSEC is enabled for this domain (DNSKEY and DS present), providing additional security for DNS lookups.
✓ Signatures valid until 2026-11-05 #21

DNSKEY signatures are valid until 2026-11-05T11:14:31Z.

MX

warn

2 mail servers

Found

Priority	Host	Records	Reverse DNS
5	mail.protonmail.ch	A 185.70.42.128 A 185.205.70.128 A 176.119.200.128	mail.protonmail.ch ✓ mail.protonmail.ch ✓ mail.protonmail.ch ✓
10	mailsec.protonmail.ch	A 185.70.42.129 A 176.119.200.129 A 185.205.70.129	mailsec.protonmail.ch ✓ mailsec.protonmail.ch ✓ mailsec.protonmail.ch ✓

Checks

✓ 2 MX records #9

Found 2 MX records for this domain.
✓ All hosts resolve #10

All MX records resolve to valid IP addresses.
!

Hosts without IPv6

The following MX hosts could not be resolved to IPv6 addresses: mail.protonmail.ch, mailsec.protonmail.ch

#11
✓ Redundant MX hosts #12

Found 2 MX records, which provides redundancy for email delivery.
✓ At most 5 MX records #13

Found 2 MX records, which is within the recommended range (1-5).
✓ No localhost targets #14

No MX records pointing to localhost found.
✓ No private IP addresses #15

No MX records resolving to private IP addresses found.
✓ No CNAME targets #22

No MX records point to a CNAME.
✓ Reverse DNS confirmed #30

All 6 MX addresss have a PTR record that resolves back to them.

TLS

pass

MTA-STS enforce · TLS-RPT · DANE on 2 of 2 MX hosts

Found

MTA-STS record: v=STSv1; id=190906205100Z;
Policy URL: https://mta-sts.protonmail.com/.well-known/mta-sts.txt
Mode: enforce
Allowed MX: mail.protonmail.ch, mailsec.protonmail.ch
Max age: 604800 seconds
TLS-RPT record: v=TLSRPTv1; rua=https://reports.proton.me/reports/smtptls

DANE (TLSA records)

MX host	TLSA	DNSSEC
mail.protonmail.ch	3 1 1 76bb66711da41643… 3 1 1 6111a5698d23c89e…	Yes
mailsec.protonmail.ch	3 1 1 76bb66711da41643… 3 1 1 6111a5698d23c89e…	Yes

Checks

✓ Record published #32

MTA-STS record found with id 190906205100Z.
✓ Policy enforced #33

The MTA-STS policy is enforced and cached for 168h0m0s.
✓ All MX hosts covered #34

Every MX host matches an mx: line of the MTA-STS policy.
✓ Reports enabled #35

TLS reports are sent to: https://reports.proton.me/reports/smtptls
✓ DANE on all MX hosts #36

All 2 MX hosts publish DNSSEC-validated TLSA records.

BIMI

info

Logo declined

Found

Record: v=BIMI1; l=; a=;
Found at: default._bimi.protonmail.com

Checks

i

Logo explicitly declined

The BIMI record has empty l= and a= tags, which says the domain publishes no logo.

#38