Website Uptime Monitor
Monitor website availability and server information for any domain
503300.com
Uptime & Server Information
Current Status
Historical Data
| Date | Status | Server |
|---|---|---|
| 9/2/2026, 10:53:44 PM | Active | SLT |
| 7/16/2026, 10:20:57 AM | Active | SLT |
| 7/9/2026, 5:36:03 PM | Active | SLT |
| 5/19/2026, 10:06:06 PM | Active | SLT |
| 4/25/2026, 5:34:23 PM | Active | SLT |
| 1/29/2026, 6:47:48 AM | Inactive | Unknown |
| 1/16/2026, 1:14:55 AM | Inactive | Unknown |
| 12/31/2025, 2:21:39 PM | Inactive | Unknown |
| 12/29/2025, 6:40:45 AM | Inactive | Unknown |
| 12/24/2025, 1:21:41 AM | Inactive | Unknown |
| 12/16/2025, 12:29:11 AM | Active | SLT-MID |
| 11/30/2025, 1:00:31 AM | Active | SLT-MID |
| 11/28/2025, 9:56:20 PM | Active | SLT-MID |
| 5/16/2025, 10:59:15 PM | Active | SLT-MID |
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.