C Data Types

C Data Types

In C programming, data types are declarations for variables. This determines the type and size of data associated with variables. For example,

int myVar;

Here, myVar is a variable of int (integer) type. The size of int is 4 bytes.

Basic types

Here's a table containing commonly used types in C programming for quick access.

Type Size (bytes) Format Specifier
int at least 2, usually 4 %d, %i
char 1 %c
float 4 %f
double 8 %lf
short int 2 usually %hd
unsigned int at least 2, usually 4 %u
long int at least 4, usually 8 %ld, %li
long long int at least 8 %lld, %lli
unsigned long int at least 4 %lu
unsigned long long int at least 8 %llu
signed char 1 %c
unsigned char 1 %c
long double at least 10, usually 12 or 16 %Lf


Integers are whole numbers that can have both zero, positive and negative values but no decimal values. For example, 0-510

We can use int for declaring an integer variable.

int id;

Here, id is a variable of type integer.

You can declare multiple variables at once in C programming. For example,

int id, age;

The size of int is usually 4 bytes (32 bits). And, it can take 232 distinct states from -2147483648 to 2147483647.

float and double

float and double are used to hold real numbers.

float salary;
double price;

In C, floating-point numbers can also be represented in exponential. For example,

float normalizationFactor = 22.442e2;