indexo.dev

online4u.cz

.cz dns crawl

First seen 2026-06-01 · Last seen 2026-06-02 · ok HTTP/1.1 200 155 ms crawled 2026-06-02

CZ · 81.91.85.19 · AS39790 Web4U s.r.o.

Reputation 89/100 weak security headers dmarc monitor-only

Classifying

HTML metadata

Title
online4U.cz, s.r.o.
Description
Pomůžeme Vám se neztratit v online světě.
Language
en

Technology

Server
Apache
Fonts
  • Google Fonts

Third-party hosts loaded (2)

  • fonts.googleapis.com×2
  • maps.googleapis.com×1

Contact

Email

Registration

Registrar
REG-WEB4U
Created
2008-06-02
Expires
2027-06-01 363 days left
Updated
2025-12-08
Name servers
  • ns2.web4u.cz
  • ns.web4u.cz

DNS records live

NS
  • ns.web4u.cz
  • ns2.web4u.cz
MX
  • 10 mail.online4u.cz

Email authentication partial

SPF
v=spf1 a mx ~all
softfail (~all)
DMARC
v=DMARC1; p=none; rua=mailto:marek.cerjak@online4u.cz; ruf=mailto:marek.cerjak@online4u.cz; fo=1
policy: none (monitoring only)
DKIM
no key found at common selectors

Certificate (current)

R13
from 2026-04-23 to 2026-07-22
Expires in 50 days

Full certificate history on crt.sh ↗

HTTP security headers

Header hygiene 30/100 Checked live page: https://online4u.cz/

findings
  • missing HSTS
  • missing Content Security Policy
  • missing frame protection
  • missing content type protection
  • missing Referrer Policy
  • missing Permissions Policy

Linked from (2)