indexo.dev

web4u.cz

.cz dns crawl

First seen 2026-05-11 · Last seen 2026-05-19 · ok HTTP/1.1 200 6230 ms crawled 2026-05-16

CZ · 81.91.86.19 · AS39790 Web4U s.r.o.

Reputation 100/100

Classifying

HTML metadata

Title
Profesionální webové služby pro vaši online prezentaci - Web4U
Description
Web4u nabízí kvalitní webové služby, které umožní vaší online prezentaci posunout se o úroveň výš. Vyberte si z registrace domény, hostingu a dalších nabízených služeb.

Technology

Server
openresty
CMS
Gatsby
Analytics
  • Google Tag Manager

Third-party hosts loaded (4)

  • www.googletagmanager.com×2
  • app2.salesmanago.pl×1
  • cdnjs.cloudflare.com×1
  • www.google.com×1

Social

Registration

Registrar
REG-WEB4U
Created
2000-12-12
Expires
2026-12-16 210 days left
Updated
2023-04-17
Name servers
  • ns2.web4u.cz
  • ns.web4u.cz

DNS records live

NS
  • ns.web4u.cz
  • ns2.web4u.cz
MX
  • 10 mx.web4u.cz
TXT
  • smv=9d9c9b062c03b840
  • MS=0394720CC11BB6E64FFED5064A40D0401C20807E
  • zoho-verification=zb27107936.zmverify.zoho.eu

Email authentication strong

SPF
v=spf1 ip4:81.91.87.150 ip4:81.91.87.80 ip4:81.91.87.60 ip4:81.91.87.250 ip4:81.91.87.34/31 ip4:81.91.87.249 ip4:81.91.87.236 ip6:2001:1568:502:1::/64 ip6:2001:1568:502:2::/64 ip6:2001:1568:502:3::/64 ip6:2001:1568::7060 ip6:2001:1568::7236 ip4:77.78.104.121 ip6:2001:1528:137::a include:_spf.jupiter.salesmanago.pl -all
strict (-all)
DMARC
v=DMARC1;p=reject;sp=none;pct=100;adkim=s;aspf=r;rua=mailto:dmarc@web4u.cz;ruf=mailto:ruf@web4u.cz
policy: reject (enforced) · sp=none
DKIM
  • default: v=DKIM1; k=rsa; p=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDSlfXDDifk7dqttp8IZsS+jYJArOj/jCbXC1GL+DqteJ1IQ9+J+LUC6R0nHb46bCVnUhHXhZjR8ScdyKr41a…
selectors probed

Certificate (current)

R12
from 2026-04-17 to 2026-07-16
Expires in 57 days

Full certificate history on crt.sh ↗

HTTP security headers

Header hygiene 80/100 Checked live page: https://www.web4u.cz/

present
  • strict-transport-security
  • content-security-policy
  • x-frame-options
findings
  • missing content type protection
  • missing Referrer Policy
  • missing Permissions Policy
Header values
x-frame-options
SAMEORIGIN
content-security-policy
frame-ancestors 'self';
strict-transport-security
max-age=31536000

Links to (2)

Linked from (1)