uptime

What it does

How to write it

uptime [OPTION]...

Most used

Nothing matches this filter.

$ run as a normal user# run as root (or with sudo)

1. 1Default output

   $uptime
    10:52:01 up  2:54,  2 users,  load average: 0.15, 0.10, 0.09

   Time, run time, users, load 1/5/15 minutes.

2. 2Run time in words

   $uptime -p
   up 2 hours, 54 minutes

   Easy to read.

3. 3Boot time

   $uptime -s
   2026-10-25 07:58:12

   Did the server reboot in the night?

4. 4Load per core

   $echo "$(cut -d' ' -f1 /proc/loadavg) / $(nproc)" | bc -l

   Over 1.0 = more work than cores.

5. 5Raw load data

   $cat /proc/loadavg
   0.15 0.10 0.09 1/182 4410

   Also running/total processes and the last PID.

6. 6Watch the load

   $watch -n 5 uptime

   The 1-minute value reacts first.

7. 7On many servers

   $for h in server1 server2; do echo -n "$h: "; ssh $h uptime; done

   Quick overview.

8. 8Unexpected reboot? (security)

   $uptime -s; last -x reboot | head -3

   Compare with the change calendar.

9. 9Same line in w and top

   $w | head -1

   w and top show the uptime line first.

10. 10Alert on high load in a script

    $awk -v c=$(nproc) '$1 > c {print "high load: " $1}' /proc/loadavg

    Simple check for cron.

Nothing matches this filter.

Files

/proc/uptime

Seconds since boot.

/proc/loadavg

Load averages.

Exit codes