Website Down Checker

See whether a site was up at our last check and when it last went down.

costar.com

Uptime & Server Information

WhoisRDAPDNS RecordsCertificateUptimeDiagnosticsHistoryHide Contact Info

Current Status

Status
Active
Server Type
istio-envoy
Page Title
CoStar | # 1 Commercial Real Estate Information Company
Meta Description
CoStar, the world leader in commercial real estate information, has the most comprehensive database of real estate data throughout the US, Canada, UK and France.
Meta Keywords
Not available
Last Checked
just now
Last Status Change
Came back up — 50 days ago (9/21/2026)
Last Downtime
First seen down 51 days ago (9/20/2026), back up 50 days ago

Observed Changes

DateStatusServer
9/21/2026, 9:24:42 AMActiveistio-envoy
9/20/2026, 9:14:24 AMInactiveUnknown
9/9/2026, 8:22:16 AMActiveistio-envoy
8/19/2026, 9:58:02 PMActiveistio-envoy
8/10/2026, 3:28:44 PMActiveUnknown
8/7/2026, 11:19:15 PMActiveUnknown
8/7/2026, 11:19:15 PMActiveUnknown
7/15/2026, 5:34:29 AMActiveUnknown
6/2/2026, 5:42:36 AMActiveUnknown
5/19/2026, 12:42:11 PMActiveUnknown
5/17/2026, 1:44:12 PMActiveUnknown
5/5/2026, 2:06:32 AMActiveUnknown
4/27/2026, 3:08:44 PMActiveUnknown
4/14/2026, 4:45:52 PMActiveUnknown
4/5/2026, 12:40:55 AMActiveUnknown
4/1/2026, 12:44:34 PMInactiveUnknown
3/30/2026, 4:18:49 PMActiveUnknown
3/28/2026, 8:14:25 PMActiveUnknown
3/18/2026, 10:54:01 AMActiveUnknown
3/3/2026, 12:43:14 PMActiveUnknown
2/27/2026, 8:30:03 AMActiveUnknown
2/12/2026, 9:55:14 AMInactiveUnknown
1/31/2026, 5:55:25 AMInactiveUnknown
1/15/2026, 7:40:53 PMInactiveUnknown
1/6/2026, 8:17:05 AMInactiveUnknown
1/3/2026, 8:18:59 AMInactiveUnknown
12/8/2025, 4:19:35 PMActiveUnknown
11/28/2025, 8:04:05 PMInactiveUnknown
11/12/2025, 2:21:48 AMActiveUnknown
11/10/2025, 12:19:39 AMActiveUnknown
11/2/2025, 8:42:25 PMActiveUnknown
9/20/2025, 6:54:09 PMActiveUnknown
9/11/2025, 5:08:25 PMActiveUnknown
8/31/2025, 12:09:48 AMActiveUnknown
8/23/2025, 8:09:20 AMActiveUnknown
8/20/2025, 9:46:33 AMActiveUnknown
7/9/2025, 1:04:41 AMActiveUnknown
7/4/2025, 6:59:52 PMActiveUnknown
6/30/2025, 4:38:33 AMInactiveUnknown
6/21/2025, 2:08:54 AMActiveUnknown
6/15/2025, 12:22:34 AMActiveUnknown
6/1/2025, 6:10:43 PMActiveUnknown
5/31/2025, 2:39:45 PMActiveUnknown
5/9/2025, 2:58:54 AMActiveUnknown
5/3/2025, 11:18:42 AMActiveUnknown
3/26/2025, 4:24:44 AMActiveUnknown
3/17/2025, 7:24:33 PMActiveUnknown
3/14/2025, 8:42:14 PMActiveUnknown
3/6/2025, 8:37:29 PMActiveUnknown
2/19/2025, 5:31:06 AMActiveUnknown
2/13/2025, 5:40:26 PMActiveUnknown
1/14/2025, 3:02:49 PMActiveUnknown
1/11/2025, 8:20:52 PMActiveUnknown

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About Website Uptime Monitoring

This page shows whether we could reach a website the last time we checked it. We also keep a record of when it went down and came back, so you can see whether an outage is new or has happened before. For each site we show:

  • Website availability and response status
  • Server software and configuration
  • Meta information including titles and descriptions
  • Historical uptime patterns

What this page reports

  • Last status change: When we last saw a site switch between reachable and unreachable
  • Last downtime: When a site was most recently seen down, and whether it has come back
  • Server and meta information: The server software, page title and meta tags we last observed

We check a domain at most once a day and record an observation only when something changes, so these are the times a change was seen rather than the exact moment it happened. For continuous, minute-by-minute checks with alerting, use website monitoring.

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.