What powers 
seibu-const.co.jp?
Last seen Sep 2026 · 15 technologies across 9 categories
Analytics
Google Analytics
since Jan 2019
CDN
cdnjs
since Jan 2022
Cloudflare
since May 2022
jQuery CDN
since Feb 2022
jsDelivr
since Jan 2022
Unpkg
since Jan 2022
Font scripts
Google Font API
since Jan 2022
JavaScript libraries
Operating systems
Red Hat
since Nov 2022
Programming languages
Java
since Nov 2022
Video players
YouTube
since Jan 2019
Web server extensions
Web servers
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
- 64% desktop
- 36% phone
Japan
Where the site's Chrome visitors come from, largest estimated audience first.
Open Page Rank
3.59 / 10 · ranked #821,504 of all domains
34 referring domains · OpenPageRank
Core Web Vitals
| LCP | 0.9 s |
| INP | 25 ms |
| CLS | 0 |
| TTFB | 300 ms |
Real user p75, Chrome UX Report, Aug 2026.
Page
- Language: Japanese
- CDN: Akamai
- Weight: 5.9 MB · 125 requests
Homepage as crawled by the HTTP Archive, Sep 2026.
Organisation
- Seibu Construction
- Founded: 1941
- Country: Japan
From Wikidata (CC0).
Infrastructure
- DNS: d-53.info
- Email: securemx.jp
- Email security: no SPF record, no DMARC record, DNSSEC signed
- SSL: Let's Encrypt, RSA 2048, expires Dec 2026
- Common Crawl link graph: rank 10,310,017
DNS records as swept Oct 2026, certificate as seen Oct 2026. How the web is hosted