nethogs

Start NetHogs (default device eth0)

$ sudo nethogs

$ sudo nethogs [eth0]

$ sudo nethogs [eth0] [wlan0]

$ sudo nethogs -d [2]

$ sudo nethogs -t

nethogs [-d seconds] [-t] [-v] [device...]

nethogs is a network monitoring tool that groups bandwidth usage by process rather than by interface or protocol. It shows which processes are consuming network bandwidth in real-time.
Unlike traditional network monitors that show per-interface statistics, nethogs identifies the actual programs responsible for network traffic, making it easier to find bandwidth-hungry applications.

-d _seconds_

Delay between refreshes in seconds; default is 1

Tracemode; output to stdout continuously

View mode; cycle through views (0-2)

Number of updates before exiting

Promiscuous mode (capture all packets)

Sort by sent data

Monitor all devices

q

Quit

Sort by sent bytes

Sort by received bytes

Cycle display mode (KB/s, KB, B, MB)

Requires root privileges to capture network packets. May not accurately track all traffic on busy systems. Only monitors TCP and UDP traffic. Some short-lived connections may be missed.

nethogs was developed by Arnout Engelen as a "net top" tool that groups bandwidth by process. It fills a gap left by traditional tools like iftop and nload which show interface-level statistics.

iftop(8), nload(1), bmon(1), ss(8)