Website Uptime Monitor
Monitor website availability and server information for any domain
21cats.org
Uptime & Server Information
Current Status
Historical Data
| Date | Status | Server |
|---|---|---|
| 9/6/2026, 8:13:36 PM | Active | openresty/1.31.1.1 |
| 7/11/2026, 1:46:14 PM | Active | nginx |
| 6/21/2026, 10:44:14 AM | Active | nginx |
| 5/1/2026, 8:26:07 PM | Active | nginx |
| 4/3/2026, 6:54:09 AM | Active | nginx |
| 3/16/2026, 2:32:51 AM | Active | nginx |
| 2/21/2026, 1:19:04 AM | Inactive | Unknown |
| 2/10/2026, 4:37:23 PM | Active | nginx |
| 1/19/2026, 6:13:48 AM | Inactive | Unknown |
| 1/17/2026, 8:16:47 AM | Inactive | Unknown |
| 1/11/2026, 10:39:51 AM | Inactive | Unknown |
| 1/9/2026, 9:58:47 PM | Inactive | Unknown |
| 12/28/2025, 11:05:02 PM | Inactive | Unknown |
| 12/13/2025, 3:46:41 PM | Active | nginx |
| 11/4/2025, 6:53:12 PM | Active | nginx |
| 10/25/2025, 4:32:48 PM | Active | nginx |
| 9/16/2025, 4:12:50 AM | Active | nginx |
| 9/1/2025, 3:13:05 AM | Active | nginx |
| 8/23/2025, 6:19:32 AM | Active | nginx |
| 8/19/2025, 3:07:03 PM | Inactive | Unknown |
| 8/10/2025, 6:08:26 PM | Active | nginx |
| 8/7/2025, 5:24:56 PM | Active | nginx |
| 7/24/2025, 6:52:42 PM | Active | nginx |
| 7/23/2025, 1:12:59 PM | Active | nginx |
| 7/15/2025, 3:45:44 AM | Active | nginx |
| 7/3/2025, 9:36:17 AM | Active | nginx |
| 6/13/2025, 2:08:29 AM | Active | nginx |
| 6/10/2025, 4:58:39 PM | Active | nginx |
| 5/12/2025, 5:44:15 PM | Active | nginx |
| 4/13/2025, 1:08:21 PM | Active | nginx |
| 2/18/2025, 2:37:40 PM | Active | nginx |
| 2/13/2025, 2:40:40 PM | Active | nginx |
| 1/31/2025, 1:04:40 PM | Active | nginx |
Don't just check uptime once — watch it 24/7
This is a one-time check. Turn on monitoring and we'll watch the domains that matter to you continuously, notifying you the moment anything moves across all three signals:
Uptime
We visit the site from multiple regions worldwide and email you within minutes if it goes down, with a per-region breakdown so a real outage stands out from a regional blip.
DNS changes
We watch NS, MX, CAA, DNSSEC, CNAME and A/AAAA records, and identify the host, network, and ASN behind them, so a real migration or hijack stands out from routine noise.
TLS certificate
We warn you 30, 14, 7, and 1 days before it expires, and flag it if the issuing authority changes or the certificate is unexpectedly replaced.
Free for your first domain: uptime, DNS, and certificate together. No credit card.
About Website Uptime Monitoring
Use the Who.is uptime information to track the availability and server information of websites. This helps track:
- Website availability and response status
- Server software and configuration
- Meta information including titles and descriptions
- Historical uptime patterns
This information is valuable for website owners, system administrators, and anyone interested in monitoring website reliability and performance.
Metrics we monitor
- Uptime percentage: The percentage of time your website is accessible
- Response time: How quickly your server responds to requests
- Status codes: HTTP response codes indicating server status
Disclaimer: Who.is is not affiliated with, endorsed by, or connected to any of the domains displayed on this page. We provide this information as a public service for informational purposes only.