What powers 
vzs.cz?
Last seen Aug 2026 · 14 technologies across 11 categories
CMS
Databases
Font scripts
JavaScript libraries
Miscellaneous
Operating systems
Programming languages
Security
Web servers
Webmail
WordPress plugins
AI Crawlers
Doesn't name any of the 33 AI crawlers we track in its robots.txt. Catch-all rules (User-agent: *) restrict some paths for every crawler, AI or not. Checked Sep 2026.
- robots.txt found
- llms.txt found
- ai.txt not found
AI Crawlers
No AI crawlers blocked
Standards: llms.txt
Audience
Czechia
Where the site's Chrome visitors come from, largest estimated audience first.
Open Page Rank
3.76 / 10 · ranked #734,714 of all domains
37 referring domains · OpenPageRank
Core Web Vitals
| LCP | 0.9 s |
| INP | 75 ms |
| CLS | 0 |
| TTFB | 500 ms |
Real user p75, Chrome UX Report, Aug 2026.
Page
- Language: Czech
- Weight: 1.6 MB · 78 requests
- WordPress theme: wp-vzs-theme · all themes
- Structured data: JSON-LD, OpenGraph, Twitter Cards
Homepage as crawled by the HTTP Archive, Sep 2026.
Organisation
- Vodní záchranná služba ČČK, z.s. (Vodní záchranná služba ČČK on Wikidata)
- Founded: 1968
- Country: Czech Republic
From the homepage's own structured data (Sep 2026) and Wikidata (CC0).
Infrastructure
- Hosted on Microsoft (20.101.143.223)
- DNS: wedos.com
- Email: Google Workspace
- Email security: SPF (hard fail), no DMARC record, DNSSEC signed, CAA
- SSL: Let's Encrypt, RSA 4096, expires Dec 2026
- Common Crawl link graph: rank 3,213,542, 13 hosts
- Verified with: Microsoft 365
DNS records as swept Sep 2026, certificate as seen Sep 2026. How the web is hosted
Full technology history →
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Recent changes
- dropped Modernizr Aug 2026
- dropped Breadcrumb NavXT Feb 2026
- detected Twitter Emoji (Twemoji) Dec 2025