indexo.dev

opentheory.org

.org crawl

First seen 2026-04-28 · Last seen 2026-05-18 · ok HTTP/1.1 200 2239 ms crawled 2026-05-07

Reputation 100/100

Classifying

HTML metadata

Title
open theory · offene theorie:
Description
open theory · offene theorie:

Technology

Server
Apache

Third-party hosts loaded (2)

  • www.google.com×1
  • www.w3.org×1

Registration

Registrar
CSL Computer Service Langenbach GmbH d/b/a joker.com
Created
2000-03-22
Expires
2028-03-22 672 days left
Updated
2026-01-24
Name servers
  • a.ns.nrw.net
  • b.ns.nrw.net
  • c.ns.nrw.net

DNS records live

NS
  • x.ns.joker.com
  • y.ns.joker.com
  • z.ns.joker.com

Email authentication no MX

SPF
not published
DMARC
not published
DKIM
no key found at common selectors

Certificate (current)

R12
from 2026-04-08 to 2026-07-07
Expires in 49 days

Full certificate history on crt.sh ↗

HTTP security headers

Header hygiene 50/100 Checked live page: https://opentheory.org/

present
  • strict-transport-security
findings
  • missing Content Security Policy
  • missing frame protection
  • missing content type protection
  • missing Referrer Policy
  • missing Permissions Policy
Header values
strict-transport-security
max-age=63072000;includeSubDomains

Links to (1)

Linked from (2)