C Program to Find the Size of int, float, double & char - sizeof Operator Examples

Find Sizes Using Variables

#include <stdio.h>
int main() {
    int intType;
    float floatType;
    double doubleType;
    char charType;
    printf("Size of int: %zu bytes\n", sizeof(intType));
    printf("Size of float: %zu bytes\n", sizeof(floatType));
    printf("Size of double: %zu bytes\n", sizeof(doubleType));
    printf("Size of char: %zu byte\n", sizeof(charType));
    return 0;
}

Size of int: 4 bytes
Size of float: 4 bytes
Size of double: 8 bytes
Size of char: 1 byte
        

Practice: Size Using Variables

Declaring variables of various types and using sizeof on them reveals how many bytes each type occupies.

Find Sizes Using Data Types Directly

#include <stdio.h>
int main() {
    printf("Size of int: %zu bytes\n", sizeof(int));
    printf("Size of float: %zu bytes\n", sizeof(float));
    printf("Size of double: %zu bytes\n", sizeof(double));
    printf("Size of char: %zu byte\n", sizeof(char));
    return 0;
}

Size of int: 4 bytes
Size of float: 4 bytes
Size of double: 8 bytes
Size of char: 1 byte
        

Practice: Size Using Types

Passing the type itself to sizeof avoids declaring temporary variables; it directly yields the number of bytes allocated to that type.