sizeofchar

sizeof(char) is the result of applying the sizeof operator to the character type in C and C++. By the language standard, sizeof(char) is defined to be 1, meaning a char occupies one byte of storage. A byte is the basic unit used to measure the size of a char, and the number of bits in a byte is given by CHAR_BIT, which must be at least 8. Therefore, a char is one byte, but that byte can be 8 or more bits depending on the platform.

There are three related types: char, signed char, and unsigned char. All three have the same size in bytes (so sizeof(char), sizeof(signed char), and sizeof(unsigned char) are all 1 on every conforming implementation), but they differ in value range and signedness. The signedness of plain char is implementation-defined: it may be either signed char or unsigned char on a given system. The ranges are defined by macros such as CHAR_MIN, CHAR_MAX, SCHAR_MIN, and UCHAR_MAX, and by CHAR_BIT for the bit width.

In practice, char types are used to store small integers and raw byte data. char is also commonly used for text processing, with strings represented as arrays of char. When portability or explicit bit width is important, developers may prefer unsigned char for raw bytes and to consult CHAR_BIT for bit-level calculations. Since sizeof(char) is always 1, it is a reliable basis for computing the size of arrays of char, but it does not by itself convey the number of bits in a character on a given platform.