C Academy · Lesson

Characters as Integers

ASCII values.

Characters Are Numbers

In C, a char is just a small integer. Every character has a numeric value defined by the ASCII table.

The letter 'A' is stored as the number 65, 'B' is 66, and so on.

#include <stdio.h>

int main(void) {
    char c = 'A';
    printf("The character %c has value %d\n", c, c);
    return 0;
}

Use the %d format specifier to print a char as its integer value, and %c to print it as a character.

The same variable can be viewed both ways.

#include <stdio.h>

int main(void) {
    char letter = 'z';
    printf("As char: %c\n", letter);
    printf("As int:  %d\n", letter);
    return 0;
}