How to use
- Enter a domain or IP and click Trace. To see the path from our server back to you, click Trace to my IP.
- Each row is one router on the way, starting at hop 1, with its address, location and ISP, and the latency of 3 probes. Known backbones get a coloured label.
- Copy results gives you the whole route to send to your host, ISP or a forum. When a domain has both IPv4 and IPv6, tick Use IPv6 for domains to trace the IPv6 route.
Options explained
- Hop
- The number of the router the packets pass through. The trace sets the packet's time to live (TTL) to 1, 2, 3 and so on. The router at hop n gets the packet just as its TTL runs out and sends back a time exceeded message, which reveals its address.
- Latency
- Each hop gets 3 probes, and the 3 round-trip times are shown in milliseconds; * means no reply to that probe. A slow hop followed by normal ones usually means that router answers these messages slowly, not that the line is slow.
- Data centre network
- Our server is in an Alibaba Cloud data centre in Shenzhen, China. The first hops are internal devices there with addresses such as 10.x, 11.x or 26.x that are not routed on the internet, so they have no location.
- Network labels
- Backbones are recognised by the address ranges their routers usually use. 202.97 is China Telecom 163 and 59.43 is China Telecom CN2. 219.158 is China Unicom 169, and 218.105 and 210.51 are China Unicom 9929. 221.176 and 221.183 are the China Mobile backbone, and 223.118–223.121 is China Mobile International (CMI).
Chinese backbones at a glance
| Network | Router addresses usually start with | Notes |
|---|---|---|
| China Telecom 163 (ChinaNet, AS4134) | 202.97 | China Telecom’s main backbone, carrying most home broadband traffic. International links often congest in the evening |
| China Telecom CN2 (AS4809) | 59.43 | China Telecom’s premium network, more stable for international traffic. “CN2 GIA” in VPS ads means the route stays on it end to end |
| China Unicom 169 (AS4837) | 219.158 | China Unicom’s main backbone |
| China Unicom 9929 (AS9929) | 218.105, 210.51 | China Unicom’s premium network for business lines |
| China Mobile CMNET (AS9808) | 221.176, 221.183 | China Mobile’s backbone |
| China Mobile International, CMI (AS58453) | 223.118–223.121 | China Mobile’s international network, common on routes to Hong Kong and Southeast Asia |
| CERNET (AS4538) | 101.4 | China’s education and research network |
These ranges are a widely used rule of thumb for reading routes, not an official allocation, so there are occasional exceptions.
Reading a route
- First hops: the data centre network (our server is at Alibaba Cloud in Shenzhen), then the ISP’s metro network.
- Middle: provincial and national backbones. The labels tell you which network the route uses. Traffic between ISPs, for example from China Telecom to China Unicom, crosses at backbone interconnects.
- Leaving China: latency jumps on the international leg, for example from about 10 ms to over 100 ms. That is distance, and it is normal.
- One slow hop, then normal ones: that router is just slow to answer. Only when latency rises at some hop and stays high for every later hop is that part of the route congested or taking a detour.
Return routes
Trace to my IP shows the path from our data centre in Shenzhen back to your connection, which is the route return traffic takes when you use servers in southern China. Home routers usually ignore ping, so the last hops may show No reply, or the target may not reply at all. That is normal.
To check an overseas VPS, enter its IP to see the outbound route from Shenzhen to the VPS. For its return route to China, run traceroute or mtr on the VPS itself towards an address in China.
To look up a single IP, use IP Lookup. To check whether a port is reachable, use Open Port Checker. To test your own NAT type and IPv6, use NAT Type Test.
Frequently asked questions
Does this show the route from my own computer?
No. The trace starts at our server in Shenzhen, not on your device. To see your own route, run tracert on Windows or traceroute on macOS and Linux. This tool shows how traffic from southern China reaches a site or an overseas server, and the return route from China back to your IP.
Why do some hops show No reply?
Many routers do not send time exceeded messages, or limit how many they send per second, for security or to save resources. As long as later hops or the target reply, packets are passing through that hop normally.
The target did not reply. Is the site down?
Not necessarily. Many servers, firewalls and home routers ignore ping, so the trace stops at the last router that answered. To check whether a site works, an HTTP or port check is more reliable.
How is this different from tracert on my computer?
The method is the same, ICMP echo requests with a growing TTL. tracert waits for each hop in turn and often takes half a minute. Here the probes for all 30 hops go out at once, in 3 rounds, so results come back in about 3 seconds. Each hop's location and ISP are also looked up, and backbones are labelled.
How do I tell CN2 GIA from CN2 GT when testing a VPS?
If the return route uses 59.43 addresses all the way, it is usually CN2 GIA. If it goes through 202.97 (the 163 backbone) and only enters 59.43 just before leaving China, it is most likely CN2 GT. This is a rule of thumb; your host's description is the final word.
Privacy
This tool needs our server: what you enter or upload is sent over HTTPS, processed and then discarded, never stored. Server access logs record IP addresses and request URLs, used only to prevent abuse.