What powers 
rk-sys.jp?
Last seen Sep 2026 · 2 technologies across 2 categories
Analytics
Google Analytics
since Aug 2022
Web servers
Nginx
since Aug 2026
AI Crawlers
No robots.txt, so all AI crawlers are allowed by default. Checked Oct 2026.
- robots.txt not found
- llms.txt not found
- ai.txt not found
AI Crawlers
No robots.txt, all AI crawlers allowed
Audience
- 85% phone
- 15% desktop
Japan
Where the site's Chrome visitors come from, largest estimated audience first.
Open Page Rank
4.71 / 10 · ranked #306,100 of all domains
52 referring domains · OpenPageRank
Core Web Vitals
| LCP | 0.7 s |
| INP | 75 ms |
| CLS | 0 |
| TTFB | 300 ms |
Real user p75, Chrome UX Report, Sep 2026.
Page
- Weight: 0.1 MB · 5 requests
Homepage as crawled by the HTTP Archive, Oct 2026.
Infrastructure
- Hosted on AIR Air Internet Service Co.,Ltd. (210.166.73.77)
- DNS: air.ne.jp
- Email: airnet.ne.jp
- Email security: SPF (soft fail), DMARC monitor only
- SSL: JPRS, RSA 2048, wildcard, expires Dec 2026
- Common Crawl link graph: rank 9,919,068, 2 hosts
DNS records as swept Oct 2026, certificate as seen Oct 2026. How the web is hosted
Subdomains
| Host | Techs |
|---|---|
| tds.rk-sys.jp | 2 |
| rk-sys.jp | 1 |
Full technology history →
Report an incorrect detection
Recent changes
- dropped Apache HTTP Server Sep 2026
- detected Nginx Aug 2026