mdcalc.com

Observed 2026-07-13T13:47:00.598Z (27m ago). Every field below was attested with an Ed25519 signature at scan time.

Up right now

Runs onCloudflare

Email byGoogle Workspace

Registered withNameCheap, Inc.

Also usesGoogle Search ConsoleAtlassian

10 subdomains · tranco_40k

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

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

mdcalc.com

A / AAAA

104.26.7.31104.26.6.31172.67.75.135

Cloudflareserves the site

vick.ns.cloudflare.comjanet.ns.cloudflare.com

cloudflare.comanswers its DNS

aspmx2.googlemail.comalt1.aspmx.l.google.comaspmx.l.google.comalt2.aspmx.l.google.com+1 more

Google Workspacereceives its email

HTTPS probe

redirect Redirecting (3xx) 301 → https://www.mdcalc.com/

HTTP status301

Servercloudflare

TLS protocolHTTP/2

TLS issuernot observed

Behind Cloudflareyes

Response time4 ms

DNS resolutionNOERROR

Redirect chain

https://www.mdcalc.com/

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

DNS Records

A 3

104.26.7.31
104.26.6.31
172.67.75.135

MX 5

10aspmx2.googlemail.com
5alt1.aspmx.l.google.com
0aspmx.l.google.com
5alt2.aspmx.l.google.com
10aspmx3.googlemail.com

TXT 9

apple-domain-verification=ebM7I9jbWCicbK0E
v=spf1 include:_spf.google.com include:servers.mcsv.net include:_spf.paubox.com -all
google-site-verification=z8frn5BESd-X20KPHEhKpiDrpo7gz9Gx8reIJHBIAEA
linkedin-site-verification=4fdefd2e-6ae8-4e5b-9371-5d07bf6e0d0c
atlassian-domain-verification=kqUL45phdIUHsOA3D6gRUts8aepSlnH5UJK8FBqaZ1h8jYs1Goj/6yJ1CY10Ex0N
google-site-verification=ZAFax3K27FynA2oj-yIbnu66rjfQOVgN3NoSJenBLKc
google-site-verification=eQSyOHCIPicVd4zLS1IPavbFJukUWLlbWZlhndo0HMk
v=DMARC1; p=reject; pct=100; rua=mailto:re+wvjzxpsp7og@dmarc.postmarkapp.com; sp=none; aspf=r;
v=DKIM1; (detected)

NS 2

vick.ns.cloudflare.com
janet.ns.cloudflare.com

SOA 1

janet.ns.cloudflare.com dns.cloudflare.com

TLS Certificates (0)

None.

Subdomains (10)

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

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

Ed25519 Receipt

Receipt ID: e3bbade4-d266-4f5e-86ec-accf127b0a73
Output Hash: 04e07a56475948bfff05c16c3d98d6804d47d03c326b718268dfc485cc3657aa
Signature: ed25519:7bcf5d095662c76d50484e67c305baa46ade39afc8f9442f96203c6c7a479485658d1c5d80b5a72876129f3691148f2e9444a693c746c565f404c5f47108690b
Public Key: ed25519:d610d74ef18f683e5beb859d241d5e67dff0c122e8928b06bec1c2476f4ba27b
Parent: (genesis)
Plane: fast

Verify this in your browser

Permalink: https://domaindrift.io/t/mdcalc.com