Why does is-down say a site is up when I cannot reach it?

When the is-down tool shows a site as up but your browser cannot load it, the problem is almost always local: DNS cache, ISP route, or firewall.

Quick answer

Our probe runs from an external cloud region. If it says the site is up but your browser fails, the outage is between you and the site — usually local DNS, ISP routing, or a corporate firewall.

Fast checks to run

  1. Try the same URL on mobile data (bypasses your Wi-Fi + DNS)
  2. Flush DNS: ipconfig /flushdns (Windows) or sudo dscacheutil -flushcache (macOS)
  3. Try a different DNS resolver (1.1.1.1 or 8.8.8.8)
  4. Traceroute the domain and look for hops timing out
  5. Disable VPN or corporate proxy briefly

Where to find it in Lemwatch

/is-down/<domain> — compare our result to your browser.

FAQ

Can Lemwatch probe from my region?

Multi-region probes are on the paid plans — see uptime settings.

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