How to check CPU information in Linux

Accurate CPU information supports capacity planning, performance troubleshooting, and compatibility checks for software and virtualization workloads. Details such as core count, architecture, and supported instruction sets indicate how much parallel work a system can handle and which binaries are appropriate.

On Linux, most CPU metadata lives in virtual files such as /proc/cpuinfo and entries under /sys that are populated by the kernel. Command-line tools like lscpu, dmidecode, and hwinfo read those structures and present fields such as model name, frequency, cache sizes, and vulnerability status in a structured format.

Some queries require elevated privileges because firmware tables and low-level descriptors are only accessible to root. Running dmidecode with sudo exposes manufacturer and serial identifiers, while utilities like lscpu remain safe for unprivileged users and can be executed over remote shells without risk of changing configuration. Combining these tools surfaces both high-level summaries and hardware-level identifiers useful for inventory, licensing, and security auditing.

1. Open a terminal on the Linux system.
2. Display summarized CPU information.

   $ lscpu
   Architecture:                    x86_64
   CPU op-mode(s):                  32-bit, 64-bit
   Model name:                      Intel(R) Core(TM) i9-9880H CPU @ 2.30GHz
   CPU(s):                          16
   Thread(s) per core:              2
   Core(s) per socket:              8

3. Check the CPU architecture.

   $ lscpu | grep '^Architecture'
   Architecture:                    x86_64

4. Identify the CPU op-mode.

   $ lscpu | grep '^CPU op-mode'
   CPU op-mode(s):                  32-bit, 64-bit

   64 bit processors can run both 64 and 32 bit operating systems. Run uname -p to see whether the running Linux kernel is 64 or 32 bit.

5. Show the CPU model name and version.

   $ lscpu | grep '^Model name'
   Model name:                      Intel(R) Core(TM) i9-9880H CPU @ 2.30GHz

6. Find the CPU maker or manufacturer.

   $ sudo dmidecode --type processor | grep --max-count=1 '^Manufacturer'
   Manufacturer:                    Intel(R) Corporation

7. Determine the number of logical CPU units.

   $ lscpu | grep '^CPU(s)'
   CPU(s):                          16

8. Check the number of threads per core.

   $ lscpu | grep '^Thread(s)'
   Thread(s) per core:              2

   Multiply the number of cores per socket by the number of threads per core to obtain the total number of logical threads available.

9. Identify known CPU vulnerabilities reported by the kernel.

   $ lscpu | grep --after-context=10 '^Vulnerabilities'
   Vulnerabilities:       
     Itlb multihit:       Not affected
     L1tf:                Not affected
     Mds:                 Not affected
     Meltdown:            Not affected
     Mmio stale data:     Not affected
     Retbleed:            Not affected
     Spec store bypass:   Mitigation; Speculative Store Bypass disabled via prctl
     Spectre v1:          Mitigation; __user pointer sanitization
     Spectre v2:          Not affected
     Srbds:               Not affected
     Tsx async abort:     Not affected
   ##### snipped #####

   Actual vulnerability fields depend on CPU model, microcode, and kernel version; mitigation status is determined by the running system.

10. Check the current CPU speed.

    $ lscpu | grep '^CPU MHz'
    CPU MHz:                         2304.000

    Related: How to check CPU clock speed in Linux

11. Retrieve the CPU ID or serial number.

    $ sudo dmidecode --type processor | grep --max-count=1 'ID:'
    ID:                              ED 06 09 00 FF FC 8B 1F

    The CPU ID is unique to each processor package on the system and is often used for identification or licensing checks.