What powers 4s21.com?
Last seen Jan 2024 · 4 technologies across 4 categories
Editors
DreamWeaver
since Jan 2024
Operating systems
CentOS
since Jan 2024
Programming languages
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
Open Page Rank
3.30 / 10 · ranked #1,132,175 of all domains
106 referring domains · OpenPageRank
Infrastructure
- Hosted on TFN-TW Taiwan Fixed Network, Telco and Network Service Provider. (60.199.193.224)
- DNS: f1.com.tw
- Email: 4s21.com
- Email security: no SPF record, no DMARC record
- Common Crawl link graph: rank 3,928,545, 1,028 hosts
DNS records as swept Oct 2026. How the web is hosted