C Program to print all ASCII values.

ASCII (American Standard Code for Information Interchange) is a character encoding standard that assigns numeric values to characters. In C programming, we can print ASCII values of characters using format specifiers without explicitly converting characters to integers.

Syntax

printf("%c \t %d<br>", i, i);

Method 1: Printing ASCII Values from A to z (65 to 122)

This example prints ASCII values for uppercase letters, special characters, and lowercase letters −

#include <stdio.h>

int main() {
    int i;
    printf("Character \t ASCII Value<br><br>");
    
    // Print ASCII values from A to z
    for (i = 65; i <= 122; i++) {
        printf("%c \t\t %d<br>", i, i);
    }
    return 0;
}

Character 	 ASCII Value

A 		 65
B 		 66
C 		 67
D 		 68
E 		 69
F 		 70
G 		 71
H 		 72
I 		 73
J 		 74
K 		 75
L 		 76
M 		 77
N 		 78
O 		 79
P 		 80
Q 		 81
R 		 82
S 		 83
T 		 84
U 		 85
V 		 86
W 		 87
X 		 88
Y 		 89
Z 		 90
[ 		 91
\ 		 92
] 		 93
^ 		 94
_ 		 95
` 		 96
a 		 97
b 		 98
c 		 99
d 		 100
e 		 101
f 		 102
g 		 103
h 		 104
i 		 105
j 		 106
k 		 107
l 		 108
m 		 109
n 		 110
o 		 111
p 		 112
q 		 113
r 		 114
s 		 115
t 		 116
u 		 117
v 		 118
w 		 119
x 		 120
y 		 121
z 		 122

Method 2: Printing All ASCII Values (0 to 255)

To print all possible ASCII values including control characters, digits, and extended ASCII −

#include <stdio.h>

int main() {
    int i;
    printf("ASCII Value \t Character<br><br>");
    
    // Print all ASCII values from 0 to 255
    for (i = 0; i < 256; i++) {
        if (i >= 32 && i <= 126) {
            printf("%d \t\t %c<br>", i, i);
        } else {
            printf("%d \t\t [Non-printable]<br>", i);
        }
    }
    return 0;
}

Key Points

• The %c format specifier prints the character representation of an integer.
• The %d format specifier prints the integer value (ASCII code).
• ASCII values 32-126 represent printable characters.
• Values 0-31 and 127-255 are control or extended characters.

Conclusion

Printing ASCII values in C is straightforward using format specifiers. The same integer can be displayed as both a character and its numeric ASCII value using %c and %d respectively.