How do I determine if I am running 32 bit or 64 bit? [duplicate]

I know at least 2 ways. Open a terminal(Ctrl+Alt+T) and type:

1. uname -a

   Result for 32-bit Ubuntu:

   Linux discworld 2.6.38-8-generic #42-Ubuntu SMP Mon Apr 11 03:31:50 UTC 2011 i686 i686 i386 GNU/Linux

   whereas the 64-bit Ubuntu will show:

   Linux discworld 2.6.38-8-generic #42-Ubuntu SMP Mon Apr 11 03:31:50 UTC 2011 x86_64 x86_64 x86_64 GNU/Linux

   Shorter version:

   $ uname -i
   x86_64
   

   or

2. file /sbin/init

   Result for 32-bit Ubuntu:

   /sbin/init: ELF 32-bit LSB shared object, Intel 80386, version 1 (SYSV), dynamically linked (uses shared libs), for GNU/Linux 2.6.15, stripped

   whereas for the 64-bit version it would look like:

   /sbin/init: ELF 64-bit LSB shared object, x86-64, version 1 (SYSV), dynamically linked (uses shared libs), for GNU/Linux 2.6.15, stripped

   Same for systems using systemd (16.04):

   file /lib/systemd/systemd

   Result for 64-bit:

   /lib/systemd/systemd: ELF 64-bit LSB shared object, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, for GNU/Linux 2.6.32, BuildID[sha1]=54cc7ae53727d3ab67d7ff5d66620c0c589d62f9, stripped

Ubuntu 12.04+ with Unity

• Hit Command(mac) or Window key.
• Type Details, and select "Details" icon
• Read "OS type" field
• 64 bit OS will read "64-bit"

Alternative to get the above screen:

• click System Menu (gear at top right corner)
• click "About this Computer"

I know the terminal responses are good but I guess this is the GUI answer. :)

Ubuntu 11.04 with Unity

• Hit Command(mac) or Window key.
• Type System info, and select System Info icon
• Read "OS type" field
• 64 bit OS will read "64-bit"

A very easy and short way is:

Open the Terminal, write the following and press Enter.

getconf LONG_BIT

The resulting number (in my case 64) is the answer.

Reference: How Do I Know if I’m Running 32-bit or 64-bit Linux?

Use the command:

uname -m

You will typically get:

i686

for 32-bit (or possibly i586 or i386), and:

x86_64

for 64-bit.

Open terminal and try the arch command. If its output is x86_64 then it's 64 bit. If it says i686, i386, etc. then it's 32 bit.

However, the best way to determine the architecture is to run the arch command and google the output.