🚀⚡Beginner

Find Size of int, float, double, char

Find size of data types using sizeof

The sizeof operator is a compile-time unary operator that returns the size (in bytes) of a data type or variable. It helps understand memory allocation and is essential for dynamic memory management.

📚 What You'll Learn

•Using the sizeof operator
•Memory sizes of different data types
•Difference between 32-bit and 64-bit systems

📝 Syntax

sizeof(data_type) or sizeof(variable)

Returns: size_t (unsigned integer)

C Program to Find Size of Data Types

size_of_types.c

1#include <stdio.h>
2
3int main() {
4    // Character type
5    printf("Size of char:      %lu byte\n", sizeof(char));
6    
7    // Integer types
8    printf("Size of short:     %lu bytes\n", sizeof(short));
9    printf("Size of int:       %lu bytes\n", sizeof(int));
10    printf("Size of long:      %lu bytes\n", sizeof(long));
11    printf("Size of long long: %lu bytes\n", sizeof(long long));
12    
13    // Floating-point types
14    printf("Size of float:     %lu bytes\n", sizeof(float));
15    printf("Size of double:    %lu bytes\n", sizeof(double));
16    
17    // Pointer size (system dependent)
18    printf("Size of pointer:   %lu bytes\n", sizeof(int*));
19    
20    return 0;
21}

Output

Size of char: 1 byte

Size of short: 2 bytes

Size of int: 4 bytes

Size of long: 8 bytes

Size of long long: 8 bytes

Size of float: 4 bytes

Size of double: 8 bytes

Size of pointer: 8 bytes

📖 Code Explanation

Code	Explanation
sizeof(char)	Returns size of char type (always 1 byte)
sizeof(int)	Returns size of int (typically 4 bytes)
%lu	Format specifier for unsigned long (size_t)
sizeof(int*)	Size of a pointer (depends on system architecture)