Show the local ARP table on Windows (find devices on your LAN)
Display the IP-to-MAC address cache Windows built by talking to neighbors — a quick way to spot which devices are on your subnet.
01Command
$ arp -a02What it does
Whenever Windows talks to another device on the local subnet, it records the IP-to-MAC mapping in the ARP cache. `arp -a` dumps this table per interface, so after pinging the broadcast address or just browsing normally, you'll see printers, phones, and routers listed. Entries expire after a few minutes of inactivity, so the list reflects recent traffic only. To remove a stale or spoofed entry, use `arp -d <ip>` or clear all with `arp -d *`.
03Risk
04Undo
✓No undo needed — this command does not change persistent state.
05Sources
- arp | Microsoft LearnEvidence: Microsoft documents that 'arp /a' (or -a) displays current arp cache tables for all interfaces, mapping IP addresses to MAC addresses.
- ARP - Windows CMDEvidence: SS64 explains arp -a shows the Address Resolution Protocol cache for every interface, with -d to delete entries.
Last verified: 2026-09-17 · Category: Network
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