ping and traceroute on Mac: Diagnose Network Issues

When pages won't load, the useful question isn't "is the internet down" — it's where it's down. ping tells you whether a machine answers and how fast; traceroute shows every router between you and it. With those two commands you can usually name the failing layer in under a minute.

Test reachability with ping

# Send 5 pings and stop
ping -c 5 1.1.1.1

# Ping by name — this also exercises DNS
ping -c 5 apple.com

Each reply prints a time= value in milliseconds — the round trip from your Mac to that machine and back. Without -c, ping runs until you press Control–C. What to look for in the summary:

• Packet loss — 0% is normal. The occasional lost packet on Wi-Fi happens; consistent loss of a few percent or more means real trouble.
• Latency — under ~20 ms to a nearby server is typical on a wired or healthy Wi-Fi connection. Steady numbers matter more than low ones: 40 ms every time is fine, 15 ms spiking to 400 ms is not.
• "Request timeout" — the machine didn't answer at all. If every ping times out, that target (or your path to it) is unreachable.

One caveat before you declare a site dead: ping uses ICMP, and some servers and firewalls deliberately ignore it while serving web traffic perfectly well. A single unresponsive target proves little — try a second one before concluding anything. On the flip side, a long-running ping is a great live Wi-Fi meter: leave ping 1.1.1.1 going while you walk around with your MacBook and watch the latency and loss rise in the dead spots.

Trace the path with traceroute

# Show every router hop between you and the destination
traceroute apple.com

Each numbered line is one router along the path, with three response times per hop. Hop 1 is your own router; the next few belong to your ISP; the rest are the wider internet. Two things trip people up when reading it:

• A * is not automatically a failure. Many routers deprioritize or ignore traceroute probes. A hop of asterisks in the middle, with later hops responding normally, means that router is just quiet — the path is fine.
• Look for where things change and stay changed. Latency that jumps at hop 3 and remains high through the rest of the trace points at the link between hops 2 and 3. Responses that stop entirely and never resume mark where the path dies.

Isolate the failing layer

The real diagnostic power is running ping against three targets in order:

1. Ping your router. Find its address under System Settings → Wi-Fi → Details… → TCP/IP (usually something like 192.168.1.1). If this fails, the problem is your Wi-Fi or local network — the internet beyond it is irrelevant.
2. Ping 1.1.1.1. If the router answers but a public IP doesn't, the problem sits with your modem or ISP.
3. Ping apple.com. If IPs work but names fail with "cannot resolve", the network is fine and DNS is broken — flush the cache or change resolvers rather than rebooting the router.

That three-step ladder — local, internet, DNS — turns "the internet feels broken" into a specific, fixable diagnosis. If the results seem inconsistent, repeat the ladder on Ethernet or from a spot next to the router: intermittent Wi-Fi can make any single run misleading, and confirming a failure twice is what separates a real diagnosis from a coincidence.

If DNS turned out to be the culprit

Step 3 failing while steps 1 and 2 pass is the classic sign of a resolver problem. Before blaming your ISP's DNS forever, try changing your Mac's DNS servers to a public resolver like 1.1.1.1 or 8.8.8.8 — it's a two-minute change in System Settings and often fixes both reliability and speed.