What powers isis.cz?
Last seen Sep 2026 · 17 technologies across 10 categories
Analytics
Font scripts
Google Font API
since Nov 2022
JavaScript libraries
Maps
Google Maps
since Nov 2022
Miscellaneous
Open Graph
since Nov 2022
PWA
since Nov 2022
Operating systems
Windows Server
since Mar 2024
Programming languages
Security
HSTS
since Mar 2024
UI frameworks
Bootstrap
since Mar 2024
Web servers
AI Crawlers
No robots.txt, so all AI crawlers are allowed by default. Checked Sep 2026.
- robots.txt not found
- llms.txt not found
- ai.txt not found
AI Crawlers
No robots.txt, all AI crawlers allowed
Audience
- 90% phone
- 10% desktop
Czechia
Where the site's Chrome visitors come from, largest estimated audience first.
Open Page Rank
1.77 / 10 · ranked #4,508,982 of all domains
4 referring domains · OpenPageRank
Core Web Vitals
| LCP | 1 s |
| INP | 75 ms |
| CLS | 0 |
| TTFB | 300 ms |
Real user p75, Chrome UX Report, Sep 2026.
Page
- Language: English
- Weight: 0.6 MB · 50 requests
- Structured data: OpenGraph
Homepage as crawled by the HTTP Archive, Oct 2026.
Infrastructure
- Hosted on WEB4U (81.91.86.10, IPv6)
- Email: MailChannels
- Email security: no SPF record, no DMARC record, DNSSEC signed
- SSL: Let's Encrypt, ECDSA P384, expires Oct 2026
- Common Crawl link graph: rank 13,950,727, 4 hosts
DNS records as swept Sep 2026, certificate as seen Sep 2026. How the web is hosted
Subdomains
| Host | Techs |
|---|---|
| www.isis.cz | 13 |
| objednani.isis.cz | 5 |
| zssjaromer.isis.cz | 5 |