You can also check the alphabet using the ASCII values of characters like this: if((ch >= 97 && ch <= 122) || (ch >= 65 && ch <= 90)) printf("The entered character %c is an Alphabet",ch); else printf("The entered character %c is not an Alphabet",ch); The ASCII value of 'a' is 97, 'z' is 122, 'A' is 65 and 'Z' is 90.