Hop details
- Hostname
- Address
- Status
- Sent
- Recv
- Loss %
- Best
- Avg
- Worst
- Last
- StDev
- Jitter
Path Trace
Watch packet loss and latency at each hop. ICMP probes leave your computer through the local agent.
ICMP probes leave your computer through the local agent. Hop results stay on this page.
Local agent
Paste the current code from the agent window. The field is cleared after each attempt.
Agent disconnected
Set up the agent
Download and start the local agent, then come back to this page.
About the agent and download- Start MyDevTools Agent. On Linux, ICMP needs the ping group range or CAP_NET_RAW.
- Copy the pairing code from the agent window.
- Paste the code below. If the browser asks for local-network access, allow it for this connection.
Private, loopback and LAN targets are blocked by default. Restart the agent with --allow-private only when you intentionally need them. Routers seen along a path are shown even when they use a private address. Pairing adds icmp.trace and keeps capabilities already granted in this browser; it never grants a scanner.
The browser sends the target and probe settings only to the agent on 127.0.0.1. ICMP probes go from the agent onto the network, so the target and the routers on the path can see this computer. MyDevTools servers do not receive the target or the hop table. This browser remembers recent targets and these settings. It does not store hop results or the pairing code.
Target
One host name or IP address. The first resolved address is probed. Routers on the path are shown even when their address is private.
Milliseconds between probes, from 200 to 60000. The next probe waits out the remainder of the interval. Default 1000.
ICMP payload size, from 0 to 1472 bytes. Don't Fragment stays on. Default 64.
How many hops to probe, from 1 to 64. Probes stop at the destination. Default 30.
How long each probe waits, from 100 to 30000 ms. Default 5000.
Automatic lets the computer choose. The list is this computer's own addresses, not neighbors on the network.
Idle
Path trace
| Hostname | Nr | Loss % | Sent | Recv | Best | Avg | Worst | Last | StDev | Jitter | Status |
|---|
On this page
Path Trace sends continuous ICMP echo probes from the MyDevTools local agent on your computer and shows loss and latency at each hop. The browser never sends ICMP itself. The agent grants icmp.trace separately from http.request.
Detailed Functionality
The table updates while the trace runs. Each hop records packets sent and received, loss, and the last, best, average and worst round-trip time, the sample standard deviation, and the average jitter. A silent hop shows “No response” and keeps an empty address. A router answer stays visible, including a home gateway or a CGNAT address in 100.64.0.0/10. Those addresses are observations of the path. They are not new targets. The host you type is checked on its own: private and loopback targets need --allow-private, and metadata, link-local and multicast targets are always refused. Probes stop at the destination or when the same router repeats at the end of the path. Copy or download the current table as text or HTML. The agent does not write that report to disk. Recent targets and the interval, payload size, hop limit, timeout and name-resolution setting stay in this browser. Hop results are not stored.
Practical Examples
1.1.1.1traces a public resolver with a 64-byte payload, 30 hops and a 5 second probe timeout.example.comresolves through the computer's DNS, then probes the first address only.127.0.0.1needs the agent started with--allow-private.
How to Use This Tool
Start the local agent
Download the agent, start it, and copy the pairing code. On Linux, ICMP needs the ping group range or CAP_NET_RAW.
Pair path tracing
Paste the code and connect. The page asks for icmp.trace and keeps capabilities this browser already holds, such as http.request.
Trace a host
Enter one host name or IP address, adjust the interval, payload, hop limit and timeout if you need to, then press Start. Press Stop to finish. The last snapshot stays on the page.
Copy the report
Select a hop to read its ICMP status. Copy or download the table as text or HTML.
Tips and Best Practices
- Loss is an integer. Before any probe is sent it is 0. After that it is 100 minus 100 times received divided by sent.
- A missing round-trip time is a dash, not zero.
- Standard deviation and average jitter appear after two replies, in tenths of a millisecond. A timeout is not a sample. Jitter is the running mean of the absolute gap between consecutive replies.
- Turn off name resolution to keep the numeric address in the host column.
- The agent runs at most two traces at once. Each desktop window starts its own trace.
- The published Windows download may be older than this page. Path tracing needs an agent that advertises icmp.trace.
- Find path MTU sends DF probes and keeps the largest size that earns an echo. A lost probe is not a size limit. The search stops at 1500 bytes.
- Source lists this computer's own addresses. Automatic lets the operating system choose. The list is not a scan and not an ARP table.