Storage of integer and character values in C

We have used the integer and character variables many times in our program. Here we will see how they are stored in the memory.

In C the character values are also stored as integers. When we assign a value larger than the character range to a char variable, overflow occurs and only the lower 8 bits are stored.

Syntax

char variable_name = value;
int variable_name = value;

Example: Character Overflow Behavior

In the following code, we shall put 270 into a character type data. The binary equivalent of 270 is 100001110, but char takes only the rightmost 8-bits. So the result will be (00001110), that is 14 −

#include <stdio.h>

int main() {
    char x = 270;
    char y = -130;
    printf("The value of x is: %d
", x);
    printf("The value of y is: %d
", y);
    return 0;
}

The value of x is: 14
The value of y is: 126

How It Works

For variable x = 270:

• 270 in binary: 100001110 (9 bits)
• char stores only 8 bits: 00001110
• Result: 14 in decimal

For variable y = -130:

• -130 is stored using 2's complement method
• 130 in binary: 10000010
• 2's complement: flip bits (01111101) + 1 = 01111110
• Only rightmost 8 bits stored: 01111110 = 126

Key Points

• char variables store values in the range -128 to 127 (signed)
• Values outside this range cause overflow and wrap around
• Negative numbers use 2's complement representation

Conclusion

Character variables in C store integer values using 8 bits. When values exceed the char range, only the lower 8 bits are preserved, causing overflow behavior that follows predictable binary arithmetic rules.