W3C · Domain Security

W3C Domain Security

Domain security

Domain security posture for W3C, probed live across 3 host(s) and 2 registrable domain(s). 3 host(s) serve HTTPS (up to TLSv1.3); 2 advertise HSTS. Email/DNS controls: DNSSEC absent, SPF present, DMARC present (p=reject).

AccessibilityStandardsWebWeb Standards

Transport & Host Security

www.w3.org

HTTPS: yes · TLS: TLSv1.3 · HSTS: yes · cert expires: Oct 7 03:48:25 2026 GMT

api.w3.org

HTTPS: yes · TLS: TLSv1.3 · HSTS: no · cert expires: Oct 7 03:48:25 2026 GMT

html.spec.whatwg.org

HTTPS: yes · TLS: TLSv1.2 · HSTS: yes · cert expires: Aug 23 02:20:30 2026 GMT

Domain (DNS/Email) Security

w3.org

DNSSEC: no · SPF: yes · DMARC: yes (p=reject) · CAA: yes

whatwg.org

DNSSEC: no · SPF: yes · DMARC: no · CAA: none

Source

Domain Security

generated: '2026-07-11'
method: probed
source: live DNS/TLS/HTTP probes of apis.yml + OpenAPI hosts
hosts:
- host: www.w3.org
  https: true
  tls_version: TLSv1.3
  cert_expires: Oct  7 03:48:25 2026 GMT
  hsts: true
  hsts_max_age: 15552000
- host: api.w3.org
  https: true
  tls_version: TLSv1.3
  cert_expires: Oct  7 03:48:25 2026 GMT
  hsts: null
- host: html.spec.whatwg.org
  https: true
  tls_version: TLSv1.2
  cert_expires: Aug 23 02:20:30 2026 GMT
  hsts: true
  hsts_max_age: 63072000
domains:
- domain: w3.org
  dnssec: false
  caa:
  - 0 issue "sectigo.com"
  - 0 issue "ssl.com"
  - 0 issuewild "comodoca.com"
  - 0 issuewild "digicert.com; cansignhttpexchanges=yes"
  - 0 issuewild "letsencrypt.org"
  - 0 issuewild "pki.goog; cansignhttpexchanges=yes"
  spf: true
  dmarc: true
  dmarc_policy: reject
- domain: whatwg.org
  dnssec: false
  caa: []
  spf: true
  dmarc: false

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