substack.com

Observed 2026-07-15T08:51:16.750Z (44m ago). Every field below was attested with an Ed25519 signature at scan time.

Guarded by a firewall

Runs onCloudflare

Email byGoogle (SPF sender)

Registered withAmazon Registrar, Inc.

Also usesGoogle Search ConsoleFacebook/Meta

IPv6 · 96 subdomains · media

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

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

substack.com

A / AAAA

172.64.150.56104.18.37.2002606:4700:4404::6812:25c82606:4700:4401::ac40:9638

Cloudflareserves the site

lee.ns.cloudflare.comali.ns.cloudflare.com

cloudflare.comanswers its DNS

mxb.mailgun.orgmxa.mailgun.org

Google (SPF sender)receives its email

HTTPS probe

rate_limited Rate limited us (429) 429 Too Many Requests - rate limited

HTTP status429

Servercloudflare

TLS protocolHTTP/2

TLS issuernot observed

Behind Cloudflareyes

Response time128 ms

DNS resolutionNOERROR

Every field above is part of the same signed observation as the records below. Blank means not observed, never "none".

DNS Records

A 2

172.64.150.56
104.18.37.200

AAAA 2

2606:4700:4404::6812:25c8
2606:4700:4401::ac40:9638

MX 2

10mxb.mailgun.org
10mxa.mailgun.org

TXT 11

google-site-verification=SXEl7_p4SBszcanSWwVc_3-RFky80c0-94janbeeWI4
tiktok-developers-site-verification=A9XRSo8lWy5CPFJ0bqI04KCpUZGAAq7p
google-site-verification=4V_X38Yf0J4VJcWFwtG38bOS1nkOWeIWJhticlMgNQE
google-site-verification=vQEKLOUDfKNOQAv9W3EUMiRD6e5ibAEPhc2yCzP7big
tiktok-developers-site-verification=7PgqCAJ52ILLOqf2KELd8uaRfJpuzaLQ
google-site-verification=DAkdykID6WqQM6tT7IfSu9_uB7-qIdB039MA_C3T3eA
google-site-verification=FfNIQIxsRHpj3Y7E_d3N6GFqGgWDZ-sfYojqCilwtqE
facebook-domain-verification=8vbxp2ntmkudc6is3h5r840c9fwo7f
v=spf1 include:_spf.google.com include:mailgun.org include:mail.zendesk.com ~all
v=DMARC1; p=reject; pct=100; rua=mailto:re+kvnosxqvppz@dmarc.postmarkapp.com; sp=reject; aspf=r;

NS 2

lee.ns.cloudflare.com
ali.ns.cloudflare.com

SOA 1

ali.ns.cloudflare.com dns.cloudflare.com

TLS Certificates (0)

None.

Subdomains (96)

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 substack.com. It updates itself. It attests a signed observation - not that the site is safe.

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

Ed25519 Receipt

Receipt ID: df919905-1836-4e1f-98ec-91b2a1451e10
Output Hash: 240b4bb87d893394f2c1d429bf3f61b10452ccc1eebbfb5df7e5d56b9ea7f018
Signature: ed25519:913e6dba590b0aa5e279e3ef54245ebd9072301ad4a9de969fdc0614b104627cc966d8f1cc82b638f930c663b0c279b54f9bd3ef59bac9588e184f61c7199a08
Public Key: ed25519:d610d74ef18f683e5beb859d241d5e67dff0c122e8928b06bec1c2476f4ba27b
Parent: (genesis)
Plane: fast

Verify this in your browser

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