What powers r-4.co.jp?
Last seen Oct 2026 · 36 technologies across 19 categories
Analytics
CDN
CMS
Databases
Font scripts
Hosting
JavaScript frameworks
JavaScript libraries
Miscellaneous
Page builders
Performance
Programming languages
Security
SEO
Tag managers
UI frameworks
Web servers
WordPress plugins
WordPress themes
AI Crawlers
Blocks 1 of 33 AI crawlers we track by name in its robots.txt. Checked Oct 2026.
Training crawlers
- GPTBot 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 found
- ai.txt not found
- Sep 2026 * added to robots.txt
AI Crawlers
1 of 33 AI crawlers blocked
Standards: llms.txt
Audience
Japan
Where the site's Chrome visitors come from, largest estimated audience first.
Open Page Rank
3.05 / 10 · ranked #1,510,676 of all domains
23 referring domains · OpenPageRank
Core Web Vitals
| LCP | 1.5 s |
| INP | 50 ms |
| CLS | 0 |
| TTFB | 1200 ms |
Real user p75, Chrome UX Report, Oct 2026.
Page
- Language: Japanese
- Weight: 2.7 MB · 75 requests
- WordPress theme: r4 · all themes
- Structured data: JSON-LD, OpenGraph, Twitter Cards
Homepage as crawled by the HTTP Archive, Oct 2026.
Organisation
- 株式会社R4
From the homepage's own structured data (Oct 2026).
Infrastructure
- Hosted on Xserver (103.3.2.75)
- DNS: Xserver
- Email: r-4.co.jp
- Email security: SPF (soft fail), no DMARC record
- SSL: Let's Encrypt, RSA 2048, expires Dec 2026
- Common Crawl link graph: rank 11,113,545, 5 hosts
- Verified with: Google
DNS records as swept Oct 2026, certificate as seen Oct 2026. How the web is hosted
Subdomains
| Host | Techs |
|---|---|
| service.r-4.co.jp | 25 |
| www.r-4.co.jp | 24 |
Full technology history →
Report an incorrect detection
Recent changes
- detected Bunny Oct 2026
- dropped parcel Oct 2026
- detected Preact Oct 2026
- detected React Oct 2026
- detected styled-components Oct 2026
- dropped SWC Oct 2026
- detected parcel Aug 2026
- detected SWC Aug 2026
- dropped WordPress Super Cache Dec 2025