How to Check CPU Temperature in Linux

Most modern systems have thermal sensors built into the CPU and motherboard. Reading these sensors is essential for monitoring system health, diagnosing performance issues, and preventing thermal throttling or hardware damage.

Install lm-sensors

The standard tool for reading hardware sensors on Linux is lm-sensors. Install it on your system:

Debian/Ubuntu:

sudo apt install lm-sensors

RHEL/CentOS/Fedora:

sudo dnf install lm_sensors

Arch:

sudo pacman -S lm_sensors

After installation, run the sensor detection:

sudo sensors-detect

This interactive script probes your hardware and configures the kernel modules needed to read sensors. Answer yes to most prompts to enable detection of all available sensors.

Reading CPU Temperature

Once configured, use the sensors command to display all detected temperatures:

sensors

You’ll see output like this:

coretemp-isa-0000
Adapter: ISA adapter
Core 0:       +52.0°C  (high = +100.0°C, crit = +100.0°C)
Core 1:       +48.0°C  (high = +100.0°C, crit = +100.0°C)
Core 2:       +50.0°C  (high = +100.0°C, crit = +100.0°C)
Core 3:       +49.0°C  (high = +100.0°C, crit = +100.0°C)

Extract Specific Core Temperature

If you need to extract a single core’s temperature programmatically, use sensors -u for uniform output:

sensors -u | grep "Core 0" | grep "input" | awk '{print $2}'

For a cleaner approach with better parsing:

sensors -A -u coretemp-isa-0000 | awk '/Core 0:/{getline; print $2}'

Or using grep and cut:

sensors | grep "Core 0" | awk '{print $3}' | tr -d '°C'

Get Average CPU Temperature

To get the average temperature across all cores:

sensors -A -u | grep "input" | awk '{sum+=$2; count++} END {print sum/count}'

Monitor Temperature in Real-Time

For continuous monitoring, use watch:

watch -n 1 sensors

This refreshes the output every second.

Alternative: psensors

For a GUI alternative, install psensors:

sudo apt install psensors

Then run psensors to display a graphical interface.

Scripting Example

Here’s a practical script to log CPU temperatures:

#!/bin/bash

while true; do
    timestamp=$(date '+%Y-%m-%d %H:%M:%S')
    temp=$(sensors -A -u coretemp-isa-0000 | grep "input" | head -1 | awk '{print $2}')
    echo "$timestamp: $temp°C" >> /var/log/cpu_temp.log
    sleep 60
done

Run this in the background or via cron to periodically log temperatures for trend analysis.

Troubleshooting

If sensors returns no output or error messages:

Verify the kernel module is loaded: lsmod | grep coretemp
Load it manually: sudo modprobe coretemp
Check your BIOS settings — some systems disable sensor access
On virtual machines, sensors may not be available at all

Check Maximum Temperature Support

View the critical temperature threshold for your CPU:

sensors | grep "crit"

Most modern Intel and AMD CPUs safely handle up to 100°C, but throttling typically starts at 80-90°C depending on the processor.