What powers 
hs21.de?
Last seen Sep 2026 · 23 technologies across 13 categories
CMS
JavaScript frameworks
JavaScript libraries
LMS
Miscellaneous
Operating systems
Programming languages
Security
UI frameworks
Video players
Web frameworks
Web servers
Webmail
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 Oct 2026.
- robots.txt found
- llms.txt not found
- ai.txt not found
Top search keywords
| Keyword | Position | Est. monthly visits |
|---|---|---|
| studium fr physiotherapeuten | #83 | 0 |
| genially website | #78 | 0 |
| genially web | #71 | 0 |
| ha21 | #43 | 0 |
| hs21 | #40 | 0 |
| dr hadrych | #38 | 0 |
The site's top keywords in Google (US), with the visits each one is estimated to bring per month.
Top backlinks
Top links pointing at the site, one per source domain, strongest first. The anchor text opens the page carrying the link.
AI Crawlers
No AI crawlers blocked
Audience
- 58% desktop
- 42% phone
Germany
Where the site's Chrome visitors come from, largest estimated audience first.
Open Page Rank
5.06 / 10 · ranked #241,098 of all domains
141 referring domains · OpenPageRank
Search traffic
0 est. monthly organic visits (US)
6 keywords in Google's top 30
Core Web Vitals
| LCP | 1.2 s |
| INP | 25 ms |
| CLS | 0 |
| TTFB | 1100 ms |
Real user p75, Chrome UX Report, Aug 2026.
Page
- Language: German
- Weight: 0.6 MB · 45 requests
- Structured data: Microdata, OpenGraph, Twitter Cards
Homepage as crawled by the HTTP Archive, Sep 2026.
Organisation
- college 21
- Founded: 2004
- Country: Germany
From Wikidata (CC0).
Infrastructure
- Hosted on DSINET-ASN (81.201.148.62)
- DNS: iphh.de
- Email: hs21.de
- Email security: SPF (hard fail), DMARC monitor only
- SSL: Sectigo, RSA 4096, wildcard, expires Dec 2026
- Common Crawl link graph: rank 8,766,197, 11 hosts
- Verified with: Google, Microsoft 365
DNS records as swept Sep 2026, certificate as seen Sep 2026. How the web is hosted
Subdomains
| Host | Techs |
|---|---|
| moodle.hs21.de | 13 |
| www.hs21.de | 8 |
| campus.hs21.de | 6 |
| campusoffice.hs21.de | 6 |
| eval.hs21.de | 4 |
| mail.hs21.de | 4 |