fastmail.com

Observed 2026-07-13T00:03:51.937235536+00:00 (1d ago). Every field below was attested with an Ed25519 signature at scan time.

Up right now

Runs onCloudflare

Secured byLet's Encrypt

email_comms

Every line above is a signed observation. Check the math at the bottom of the page.

INFRASTRUCTURE MAPwhat fastmail.com actually stands on - every host below is a signed observation

fastmail.com

A / AAAA

103.168.172.65

Cloudflareserves the site

fmns1.messagingengine.comfmns2.messagingengine.com

messagingengine.comanswers its DNS

in1-smtp.messagingengine.comin2-smtp.messagingengine.com

messagingengine.comreceives its email

TLS

*.fastmail.com

Let's Encryptissued its certificate

DNS Records

A 1

103.168.172.65

MX 2

10in1-smtp.messagingengine.com
20in2-smtp.messagingengine.com

TXT 4

v=spf1 include:spf.messagingengine.com ~all
v=DMARC1; p=none; rua=mailto:e3936a44@inbox.ondmarc.com
v=spf1 include:spf.messagingengine.com ~all
v=STSv1; id=20251216T132000

NS 2

fmns1.messagingengine.com
fmns2.messagingengine.com

SOA 1

fmns1.messagingengine.com postmaster.messagingengine.com

SRV 3

autodiscover.fastmail.com:443 p0
imap.fastmail.com:993 p0
:0 p0

CAA 8

issue "comodoca.com"
issue "digicert.com; cansignhttpexchanges=yes"
issue "letsencrypt.org"
issue "pki.goog; cansignhttpexchanges=yes"
issuewild "comodoca.com"
issuewild "digicert.com; cansignhttpexchanges=yes"
issuewild "letsencrypt.org"
issuewild "pki.goog; cansignhttpexchanges=yes"

TLS Certificates (3)

Common Name	Issuer	Expires
`*.fastmail.com`	C=US, O=Let's Encrypt, CN=YR2	Sun, 30 Aug 2026 00:19:47 +0000
`YR2`	C=US, O=ISRG, CN=Root YR	Sat, 02 Sep 2028 23:59:59 +0000
`Root YR`	C=US, O=Internet Security Research Group, CN=ISRG Root X1	Thu, 02 Sep 2032 23:59:59 +0000

Subdomains (0)

None observed.

The proof

Signed at scan time. Check the math yourself. Every line above is part of one signed observation. Re-hash it and check the Ed25519 signature in your own browser; nothing leaves your machine.

Verify this receipt

Put the receipt on your own site. A live badge showing what DomainDrift observes and signs for fastmail.com. It updates itself. It attests a signed observation - not that the site is safe.

<a href="https://domaindrift.io/t/fastmail.com">
  <img src="https://domaindrift.io/badge/fastmail.com.svg"
       width="300" height="64" alt="DomainDrift signed observations for fastmail.com">
</a>

Ed25519 Receipt

Receipt ID: b00a4a23-8e42-424b-b895-48e1584019b2
Output Hash: b645503fb681dcdbc360e44e9d439e7fcc18c5af1c40b32502d15c29c91f9944
Signature: ed25519:4e7924154e68cde154697aca58bfc9b358d666eea334ec45b67054e4880aa93e5ecfc5ea86f5166b61a8d00a5768424322145e44de7795ce0dafb203c6f64900
Public Key: ed25519:178c3bd0f57d9d64b83cc4630753381e1a465005a2bbba3d032371f24af0bfd8
Parent: (genesis)
Plane: fast

Verify this in your browser

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