Correct a description, link or other detail. Submissions are reviewed before publication.
Lifeline · master.cz over time
Checked in the last 30 daysOlder, dated recordFrom registration records
On AboutUs since 2007 · 1 registrar change since Jun 2, 2009 · no registrant change on record since 2009 · last checked Jul 19, 2026.
Registration
No registration date on file yet. AboutUs reads it from RDAP when the site is checked.
AboutUs record
AboutUs wiki pageAboutUs wiki pageJun 6, 2007 – Nov 8, 2013An AboutUs wiki page described master.cz from Jun 6, 2007 to Nov 8, 2013 (2 edits).Source: AboutUs wiki archive, 2006–2023Said about itself in 2007Jul 1, 2007“Master Internet - server housing - konektivita: O Nás”Source: AboutUs wiki archive, 2007Current AboutUs record
Registrar
REG-IGNUMREG-IGNUMJun 2, 2009 – Oct 4, 2021Registrar REG-IGNUM in the WHOIS and RDAP records held for master.cz, from Jun 2, 2009 to Oct 4, 2021.Source: WHOIS / RDAP archive (who.is)REG-WEBGLOBE
Registrant
Registrant recordsJun 2, 2009 – Jun 12, 2026Registration records for master.cz are held from Jun 2, 2009 to Jun 12, 2026 (115 records). None shows a change of registrant. Privacy-service and redaction changes, renames of the same organization and new contacts at it are not counted.Source: WHOIS / RDAP archive (who.is); counted by registrant name and organization only
No registrant changes recorded, 2009–2026
Zone file
Nameservers: master.czNameservers: master.czJun 2, 2009 – Jun 12, 2026Registration records listed master.cz nameservers (dns1.master.cz, dns2.master.cz, ns1.master.cz…) for master.cz from Jun 2, 2009 to Jun 12, 2026.Source: From registration records (WHOIS / RDAP archive, who.is)
Certificate
Unizeto Technologies S.A.Unizeto Technologies S.A.Jul 14, 2025 – Aug 19, 2026Unizeto Technologies S.A. issued 2 certificates for master.cz from Jul 14, 2025, the latest valid until Aug 19, 2026.Source: Certificate Transparency logs (AboutUs's own certificate-log reader)
2010201520202025Apr ’26← last 12 months, drawn wider
Every dated fact on this lifeline (10)
Jun 6, 2007 – Nov 8, 2013AboutUs record: An AboutUs wiki page described master.cz from Jun 6, 2007 to Nov 8, 2013 (2 edits).Source: AboutUs wiki archive, 2006–2023
Jul 1, 2007AboutUs record: “Master Internet - server housing - konektivita: O Nás”Source: AboutUs wiki archive, 2007
Jun 2, 2009 – Oct 4, 2021Registrar: Registrar REG-IGNUM in the WHOIS and RDAP records held for master.cz, from Jun 2, 2009 to Oct 4, 2021.Source: WHOIS / RDAP archive (who.is)
Jun 2, 2009 – Jun 12, 2026Registrant: Registration records for master.cz are held from Jun 2, 2009 to Jun 12, 2026 (115 records). None shows a change of registrant. Privacy-service and redaction changes, renames of the same organization and new contacts at it are not counted.Source: WHOIS / RDAP archive (who.is); counted by registrant name and organization only
Jun 2, 2009 – Jun 12, 2026Zone file: Registration records listed master.cz nameservers (dns1.master.cz, dns2.master.cz, ns1.master.cz…) for master.cz from Jun 2, 2009 to Jun 12, 2026.Source: From registration records (WHOIS / RDAP archive, who.is)
Mar 3, 2022 – Jun 12, 2026
Jul 18, 2026 – Jul 19, 2026 (latest)
Authority and Safety last refreshed Jul 19, 2026.
Source: AboutUs checks
REG-WEBGLOBE
Mar 3, 2022 – Jun 12, 2026 (latest)
Registrar REG-WEBGLOBE in the WHOIS and RDAP records held for master.cz, from Mar 3, 2022 to Jun 12, 2026.
Source: WHOIS / RDAP archive (who.is)
Let's Encrypt
Apr 5, 2026 – Nov 5, 2026
Let's Encrypt issued 55 certificates for master.cz from Apr 5, 2026, the latest valid until Jan 30, 2027.
Source: Certificate Transparency logs (AboutUs's own certificate-log reader)
Asseco Data Systems S.A.Apr 24, 2026 – Nov 5, 2026Asseco Data Systems S.A. issued 4 certificates for master.cz from Apr 24, 2026, the latest valid until Apr 24, 2027.Source: Certificate Transparency logs (AboutUs's own certificate-log reader)
Registrar: Registrar REG-WEBGLOBE in the WHOIS and RDAP records held for master.cz, from Mar 3, 2022 to Jun 12, 2026.Source: WHOIS / RDAP archive (who.is)
Jul 14, 2025 – Aug 19, 2026Certificate: Unizeto Technologies S.A. issued 2 certificates for master.cz from Jul 14, 2025, the latest valid until Aug 19, 2026.Source: Certificate Transparency logs (AboutUs's own certificate-log reader)
Apr 5, 2026 – Nov 5, 2026Certificate: Let's Encrypt issued 55 certificates for master.cz from Apr 5, 2026, the latest valid until Jan 30, 2027.Source: Certificate Transparency logs (AboutUs's own certificate-log reader)
Apr 24, 2026 – Nov 5, 2026Certificate: Asseco Data Systems S.A. issued 4 certificates for master.cz from Apr 24, 2026, the latest valid until Apr 24, 2027.Source: Certificate Transparency logs (AboutUs's own certificate-log reader)
Jul 18, 2026 – Jul 19, 2026AboutUs record: Authority and Safety last refreshed Jul 19, 2026.Source: AboutUs checks
Registered 1998 · site is live · HTTPS valid
master.cz has an AboutUs profile for public website intelligence, ownership context, trust signals, monitoring, and owner verification.
AboutUs has not vetted this site. Everything below is what we could measure automatically. Anything you do on the site — paying, sharing personal details, downloading — is between you and the site, not AboutUs.
Current facts
Latest available measurements; dated entries retain their dates. These are measurements, not an endorsement of the site.
latest result
Domain registered Jan 30, 1998 — 28 years old.
latest result
Registrar on record: Webglobe, s.r.o. — unchanged since AboutUs began tracking (Nov 5, 2026).
Authority: not enough signals yetNot enough signals yet
Why we're not scoring this yet
We withhold an authority number until independent evidence (global rank, link-graph presence) has accrued. The facts we do have about this site are shown below — we'd rather say “not enough signals yet” than invent a low score.
What master.cz said about itself, 2007
Quoted from the site's AboutUs wiki page in each year it changed (1 version). These are the page's own words at the time, not AboutUs's assessment. New words · dropped words
2007
Master Internet - server housing - konektivita: O Nás
Site history
Dated record — historical facts always carry their date.
1998
Domain registered (Jan 30, 1998).
2007
First tracked by AboutUs (Jun 6, 2007); profile edited 2 times through 2013.