How To Check CPU Temperature On Linux

Your PC will automatically shut down if the CPU temperature reaches dangerous levels (usually 90°C+). But even if you don’t exceed this threshold, exposing your CPU to high temperatures can still cause damage in the long term.

So, if you regularly perform CPU-intensive tasks for extended periods, it’s a good idea to monitor the CPU temperature.

As an example, we’ve listed methods for Ubuntu in the sections below, but you can apply them to most other Linux distros as well.

Thermal Sysfs Interface

The motherboard contains multiple thermal zone devices (sensors), such as the acpitz, which is located near the CPU socket, or x86_pkg_temp, which is embedded in the CPU itself. You can monitor the temperature readings from all these sensors with the following steps:

1. Press CTRL + Alt + T to launch the Terminal and execute the following commands:
   cat /sys/class/thermal/thermal_zone*/temp
cat /sys/class/thermal/thermal_zone*/type
   
2. You can check which temperature reading corresponds to which sensor. Also, the readings will be output in millidegrees Celsius. So, 42000 m °C would be 42 °C.

Lm-sensors

Lm-sensors is an open-source tool used for monitoring system information such as CPU temperature and fan speed. Here’s how you can install and use this utility on Ubuntu:

1. Execute the following commands in the terminal:
   sudo apt install lm-sensors
/etc/init.d/kmod start
sudo sensors-detect --auto
sensors
   
2. You can also use the watch sensors command to get real-time CPU temperature data.
   

Psensor

Psensor uses the lm-sensors package we installed earlier to display the CPU temperature in graphical form. Here’s how you can use this tool:

1. Execute the following command in the terminal to install Psensor:
   sudo apt update
sudo apt install psensor
   
2. Once Psensor is installed, run it from the application launcher.
3. Select the CPU temperature and any additional stats you want to monitor.
4. From the top panel, select Sensor Preferences > Application Indicator.
5. Select the CPU core and enable the Display Sensor in the label option.
   

Glances

Glances is a popular system monitoring tool that uses a web-based interface, i.e., you can remotely monitor your machine’s stats from another device with Glances. Here’s how you can install and use this tool on Ubuntu:

1. Execute any of the following commands to install Glances:
   sudo apt install glances
$ curl -L https://bit.ly/glances | /bin/bash
$ wget -O- https://bit.ly/glances | /bin/bash
   
2. Once it’s installed, run glances from the terminal and press F to view the CPU temp and other details.
   

Via BIOS

On most modern systems, you can also check the CPU temperature via the BIOS. But we recommend using the other methods if possible. Whatever CPU-intensive task you’re doing, you’ll have to stop it and restart your PC to access the BIOS. As such, you can’t use this method to get live readings during specific parts of the task.

With that said, here are the necessary steps if you’d like to try the BIOS method anyway:

1. Restart your PC and press the BIOS Key (Fn keys or Del).
2. Navigate to the Power or similar tab and look for the Hardware Monitor. The CPU temperature, along with other details, will be listed in this section.
   

Normal and Maximum CPU Temperature

During typical usage, 70° C and anything lower is considered to be normal temperature. So, if your Linux CPU temperature falls in this range, you’re good!

During CPU-intensive tasks like gaming, video editing, or software compiling, the temperature can reach between 70°C to 80° C. This is still in the expected range, but if you regularly perform such tasks, it’s a good idea to start looking into ways to lower the CPU temperature for best performance and lifespan.

The 80° C to 90° C zone is where things get spicy. Typically this means some combination of an intensive task, overclocking, lack of cleaning, and subpar cooling systems, possibly even all. In this case, we recommend checking the section below so that you can take appropriate steps to lower the CPU temp.

Anything above 90° C is the danger zone. Most CPUs will automatically shut down the system when this threshold is exceeded. But even if it doesn’t shut down, it’s a bad idea to keep exposing the CPU to such temperatures. It is imperative that you take steps to lower the CPU temperature in this scenario. We’ve detailed how to do so in the section below.