Is there a command that returns network utilization?

ifstat doesnt require root. Run it with -S to update the current line instead of printing a new line for each measurement.

egil@mutter:~$ ifstat -S
       eth0
 KB/s in  KB/s out
    0.13      0.26

bmon runs without root:

enter image description here

If you give it the right parameters it returns only one line

bmon -o 'ascii:noheader;quitafter=1' -p wlan0
wlan0 0.00B 0.0 0.00B 0.0

maybe this helps

Try iftop...

but I think that for this you need root privileges.

Here is a shell script that prints a short line with realtime data:

#!/bin/bash

ifstat -q -i wlan0 -S 0.1 1 | perl -n -e '/(\d+\.\d+).*(\d+\.\d+)/ && print "Down: $1 KBps - Up: $2 KBps\n"'

Sample Output:

Down: 4.25 KBps - Up: 0.00 KBps

Special thanks to Egil for his answer which pointed me to ifstat.

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