why sizeof('a') is 4 in C? [duplicate]

Answer 1

The following is the famous line from the famous C book - The C programming Language by Kernighan & Ritchie with respect to a character written between single quotes.

A character written between single quotes represents an integer value equal to the numerical value of the character in the machine's character set.

So sizeof('a') is equivalent to sizeof(int)

Answer 2

Because in C character constants, such as 'a' have the type int.

There's a C FAQ about this suject:

Perhaps surprisingly, character constants in C are of type int, so sizeof('a') is sizeof(int) (though this is another area where C++ differs).

Answer 3

'a' by default is an integer and because of that you get size of int in your machine 4 bytes.

char is 1 bytes and because of this you get 1 bytes.