How to check packet loss on Windows: ping and pathping

Opening the command prompt

1. Press Win+R, type cmd and press Enter: the command prompt opens. Windows Terminal or PowerShell work too — the commands are the same.
2. A command is typed on one line and run with Enter. To stop a long-running command, press Ctrl+C.
3. Results are easy to save: select the text with the mouse and press Enter, and it is copied to the clipboard.

ping: is there loss, and what is the latency

The ping command sends small probe packets to an address and waits for replies. For each reply Windows shows the round-trip time, and at the end the statistics: how many packets were sent, received and lost, plus the minimum, maximum and average time.¹

Twenty probe packets to an address — for example, your router or a stable host on the internet:

ping -n 20 address

The -n switch sets the number of packets (four by default); -t keeps pinging until Ctrl+C — handy for catching rare loss: leave the command running for a match and look at the summary. The -l switch changes the packet size, -w sets how long to wait for a reply, and -a tries to resolve the host name from the address.¹

What counts as a problem: any lost packets on a quiet wired network, and a large gap between the minimum and maximum time. That gap is jitter, the thing the game shows as ping spikes.

Where to ping. Games usually do not show the address of the match server, but you can ping your router's address and then a stable host on the internet. If there is loss already to the router, the problem is at home; if it appears only further out, it is on the route.

pathping: at which hop packets are lost

pathping combines a route trace with ping: first it lists the hops between you and the address, then for several minutes it sends probe packets to each of them and counts what share did not come back. The result shows on which leg of the path packets go missing.²

The -n switch skips resolving hop addresses to names, and the result appears noticeably sooner:

pathping -n address

By default the command sends a hundred probes to every hop with a quarter-second pause, so you will have to wait: Microsoft describes this stage as “computing statistics”. The table has two groups of columns — loss on the path from you to the hop, and loss at the hop itself or on the link to it. Loss on a link (the rows with a vertical bar) points to a congested leg. Loss at a hop may only mean that the router is reluctant to answer probes while forwarding traffic normally.²

If loss appears at the first or second hop, it is your router or your ISP's network. If further out — other networks on the route, and nothing at home will fix them.

Checking against the game's numbers

The Windows commands check the path to the address you named, while the game measures the path to its own server. So keep both open: the network stats in the game and ping -t in the background. If the spikes line up in time, the problem is on the shared part of the path, most likely at home or at your ISP. If the game shows loss and ping is clean, the bottleneck is closer to the game server.

Where to turn on the network stats in the game: Counter-Strike 2 · Fortnite · Apex Legends · Battlefield 6 · Dota 2 · Rocket League

What to do next. Loss to the router — reseat the cable, reboot the router, get off Wi-Fi. Loss at your ISP — write to their support with the pathping results: that is concrete data, not an “it lags” complaint. Loss further along the route — the area where SLARP works: it routes the game's traffic through its own network, picks the route to the server and optimizes ping and jitter.