Traceroute

A traceroute lists the routers that your data passes on its way to a server. It sends probes with a growing hop limit, so each router on the path reveals itself when the limit runs out. The result shows the order of the routers and how long each took to answer.

That hop didn't answer our probes. Many routers and firewalls ignore them on purpose, or answer too slowly, while still passing your traffic on. A few * * * lines in the middle are normal, and a trace that ends in them doesn't mean the site is down.

Not necessarily. Plenty of servers and firewalls drop traceroute probes, so the trace stops short even though the site works. To check whether a site is up, use a website down checker, which makes a real web request.

The trace runs on our server in Germany, so it shows the route from there. It isn't your own path. To trace from your connection, run tracert example.com on Windows, or traceroute example.com or mtr example.com on macOS and Linux.

A hop with a high time is not always a problem. Routers answer probes with low priority, so one slow hop followed by fast ones is usually harmless. Times that jump and stay high until the end point to a long distance or a congested link.

Addresses like 10.x.x.x, 172.16.x.x and 192.168.x.x only exist inside a network, so there is nothing public to look up for them. We mark them as private (inside a network) and skip the lookup.

Each visitor can run 2 traces a minute and 10 an hour, and each target can be traced 10 times an hour. When a trace returned hops, we keep the result for 2 minutes, and repeat views of it don't count.

We keep a finished trace for 2 minutes so repeat views are instant, and our server logs which target was traced for 14 days so we can deal with abuse. We don't store your IP address, only a scrambled form of it.