traceroute apple.comTrace the route to apple.com, up to 64 hops, three probes per hop.
When to use it
Use traceroute when a site is slow or unreachable and you want to know where the problem starts: on your Wi-Fi, at your ISP, or near the destination. It shows each router (hop) on the path and how long each takes to answer.
Steps
Open Terminal and run traceroute
Type the command with a host name or IP address. Press Ctrl+C to stop early.traceroute -n 1.1.1.1Read each line
Each numbered line is one hop: its address and three round-trip times, one per probe. Hop 1 is your router.Look for where the times jump
Times normally grow a little with distance. A jump that continues in every later hop marks where latency is added. A jump at one hop only, with normal times after it, is just that router answering slowly.Try ICMP if the trace stalls
If you see a run of* * *and no destination, the host may ignore traceroute's default UDP probes. ICMP (-I) often gets through.traceroute -I -n apple.com
Output explained
A real trace from a Mac on home Wi-Fi (public addresses replaced with documentation ranges):
traceroute to 1.1.1.1 (1.1.1.1), 64 hops max, 40 byte packets
1 10.0.0.138 12.833 ms 8.880 ms 9.522 ms
2 100.74.95.254 11.203 ms 6.018 ms 10.584 ms
3 10.238.55.45 9.097 ms 11.600 ms
10.238.55.41 19.250 ms
4 10.238.55.46 13.069 ms 9.319 ms 10.549 ms
5 198.51.100.246 16.503 ms 15.426 ms 8.422 ms
6 * * *
7 203.0.113.149 15.439 ms
- Hop 1 (10.0.0.138) is the home router: around 10 ms over Wi-Fi.
- Hop 2 is 100.74.x.x, a carrier-grade NAT address: this ISP shares public IPs between customers.
- Hop 3 shows two addresses: the ISP balances traffic over parallel links, so probes took different paths.
- Hop 6
* * *: that router didn't reply to probes. It still forwarded traffic, because hop 7 answered. - Times stay around 10–20 ms the whole way, so this path is healthy.
Options and variations
| Flag | Meaning | Example |
|---|---|---|
| -n | Show IP addresses only; don't look up names | traceroute -n apple.com |
| -I | Use ICMP echo probes instead of UDP | traceroute -I apple.com |
| -m N | Maximum number of hops (default 64) | traceroute -m 20 apple.com |
| -q N | Probes per hop (default 3) | traceroute -q 1 apple.com |
| -w N | Seconds to wait for each reply (default 5) | traceroute -w 2 apple.com |
| -P TCP -p 443 | TCP probes to a port, for hosts that drop UDP and ICMP | sudo traceroute -P TCP -p 443 apple.com |
Common errors
| Error | Cause | Fix |
|---|---|---|
| * * * on every hop | Probes blocked by a firewall, VPN or the local network | Try -I; disconnect the VPN; test from another network. |
| traceroute: unknown host | The name didn't resolve | Check the spelling, or trace an IP address directly. |
| Trace never reaches the destination | The host or its firewall ignores probes | Normal for many servers. If the site loads, the path works. |
Do it in the app
LightAtom's traceroute draws each hop on a world map, with its router name and round-trip times. Switch between ICMP and UDP with one click.
Frequently asked questions
How do I traceroute on a Mac?
Open Terminal and run traceroute followed by a host name or IP, for example traceroute apple.com. Add -n for faster output without names, or -I to use ICMP probes.
How do I read traceroute output?
Each line is a hop with its address and three round-trip times. Look for the first hop where times jump and stay high in later hops: that's where the delay starts. Isolated slow hops and stars are usually harmless.
What is the difference between traceroute and tracert?
tracert is the Windows version. It uses ICMP by default, while macOS traceroute uses UDP unless you add -I. The output is read the same way.
Why does traceroute show stars?
A router didn't send a reply in time. Many routers rate-limit or ignore these replies but still forward your traffic, so stars in the middle of a trace are normal.
Do I need sudo for traceroute on a Mac?
Not for UDP or ICMP traces. TCP probes (-P TCP) need sudo because they use raw sockets.