file /sbin/init

/sbin/init:

 ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked

 (uses shared libs), for GNU/Linux 2.6.18, stripped

# display 64-bit Then it is 64 Bit system

file /sbin/init

/sbin/init:

 ELF 32-bit LSB executable, Intel 80386, version 1 (SYSV), for GNU/Linux

 2.2.5, dynamically linked (uses shared libs), stripped

# Display as 32 bit Then it is 32 Bit system