What powers isstbn.cz?
Last seen Aug 2026 · 7 technologies across 5 categories
JavaScript libraries
Miscellaneous
Programming languages
Security
Web servers
AI Crawlers
Blocks 1 of 33 AI crawlers we track by name in its robots.txt. Checked Sep 2026.
Training crawlers
- Webzio-Extended Blocked
The other 32 AI crawlers we track are not mentioned and only inherit the catch-all rules that apply to every crawler.
- robots.txt found
- llms.txt not found
- ai.txt not found
AI Crawlers
1 of 33 AI crawlers blocked
Audience
- 88% phone
- 12% desktop
Czechia
Where the site's Chrome visitors come from, largest estimated audience first.
Open Page Rank
2.81 / 10 · ranked #1,953,832 of all domains
11 referring domains · OpenPageRank
Core Web Vitals
| LCP | 0.7 s |
| INP | 75 ms |
| CLS | 0 |
| TTFB | 300 ms |
Real user p75, Chrome UX Report, Aug 2026.
Page
- Language: Czech
- Weight: 0.1 MB · 26 requests
Homepage as crawled by the HTTP Archive, Sep 2026.
Infrastructure
- Hosted on ZONER-AS (217.198.113.104, IPv6)
- DNS: regzone.cz
- Email: zoner.com
- Email security: no SPF record, no DMARC record, DNSSEC signed
- SSL: DigiCert, RSA 2048, expires Feb 2027
- Common Crawl link graph: rank 1,283,173, 2 hosts
- Verified with: Microsoft 365
DNS records as swept Sep 2026, certificate as seen Sep 2026. How the web is hosted