Write a Java Program to Count Vowels and Consonants in a String with an example. In this count of consonants and vowels in a string example, we first used for loop to iterate vowConsStr. Inside the loop, we assigned (ch = vowConsStr.charAt(i)) each character to ch to keep the code simple. Next, we used the Else If statement.
Within the if condition, we check whether the character is equal o a, e, i o, u, A, E, I, O, and U. If true, we increment the value of the vowel. In the else if statement, we used (ch >= ‘a’ && ch <= ‘z’ || ch >= ‘A’ && ch <= ‘Z’) to check whether the character is an alphabet. If True, we increment the consonant value. Here, we can also use else if (Character.isAlphabetic(ch)).
import java.util.Scanner; public class CountVowCons1 { private static Scanner sc; public static void main(String[] args) { String vowConsStr; int i, vowels, consonants; vowels = consonants = 0; char ch; sc= new Scanner(System.in); System.out.print("\nPlease Enter Vowel, Consonant String = "); vowConsStr = sc.nextLine(); for(i = 0; i < vowConsStr.length(); i++) { ch = vowConsStr.charAt(i); if(ch == 'a' || ch == 'e' || ch == 'i' || ch == 'o' || ch == 'u' || ch == 'A' || ch == 'E' || ch == 'I' || ch == 'O' || ch == 'U') { vowels++; } else if (ch >= 'a' && ch <= 'z' || ch >= 'A' && ch <= 'Z'){ consonants++; } } System.out.println("\nNumber of Vowel Characters = " + vowels); System.out.println("Number of Consonant Characters = " + consonants); } }

Java Program to Count Vowels and Consonants in a String using While Loop
The following toLowerCase() statement converts the given string to lowercase.
String lw_vowConsStr = vowConsStr.toLowerCase();
Instead of checking both uppercase and lowercase letters, we compare only lowercase and count the vowels and consonants.
import java.util.Scanner; public class CountVowCons2 { private static Scanner sc; public static void main(String[] args) { String vowConsStr; int i, vows, cons; i = vows = cons = 0; char ch; sc= new Scanner(System.in); System.out.print("\nPlease Enter String = "); vowConsStr = sc.nextLine(); String lw_vowConsStr = vowConsStr.toLowerCase(); while(i < lw_vowConsStr.length()) { ch = lw_vowConsStr.charAt(i); if(ch == 'a' || ch == 'e' || ch == 'i' || ch == 'o' || ch == 'u') { vows++; } else if(ch >= 'a' && ch <= 'z') { cons++; } i++; } System.out.println("\nNumber of Vowel Characters = " + vows); System.out.println("Number of Consonant Characters = " + cons); } }
Please Enter String = Tutorial gateway
Number of Vowel Characters = 7
Number of Consonant Characters = 8
In this Java Program to Count Vowels and Consonants in a String example, we compare the ASCII values instead of comparing characters.
import java.util.Scanner; public class CountVowCons3 { private static Scanner sc; public static void main(String[] args) { String vowConsStr; int i, vows, const; vows = const = 0; int cp; sc= new Scanner(System.in); System.out.print("\nPlease Enter String = "); vowConsStr = sc.nextLine(); String up_vowConsStr = vowConsStr.toUpperCase(); for(i = 0; i < up_vowConsStr.length(); i++) { cp = up_vowConsStr.codePointAt(i); if(cp == 65 || cp == 69 || cp == 73 || cp == 79 || cp == 85) { vows++; } else if(cp >= 65 && cp <= 90 || cp >= 97 && cp <= 122) { const++; } } System.out.println("\nNumber of Vowel Characters = " + vows); System.out.println("Number of Consonant Characters = " + const); } }
Please Enter String = Hello World
Number of Vowel Characters = 3
Number of Consonant Characters = 7
Java Program to Count Vowels and Consonants in a String using functions
This code to Count String Vowels and Consonants is the same as the above. Here, we separated the Vowels and Consonants logic using Java functions.
import java.util.Scanner; public class CountVowCons4 { private static Scanner sc; public static void main(String[] args) { String vowConsStr; sc= new Scanner(System.in); System.out.print("\nPlease Enter String = "); vowConsStr = sc.nextLine(); VowOrCons(vowConsStr.toLowerCase()); } public static void VowOrCons (String vowConsStr) { int i, vwl, cnts; vwl = cnts = 0; char ch; for(i = 0; i < vowConsStr.length(); i++) { ch = vowConsStr.charAt(i); if(ch == 'a' || ch == 'e' || ch == 'i' || ch == 'o' || ch == 'u') { vwl++; } else if(ch >= 'a' && ch <= 'z') { cnts++; } } System.out.println("\nNumber of Vowel Characters = " + vwl); System.out.println("Number of Consonant Characters = " + cnts); } }
Please Enter String = Hi, Howe are you 123?
Number of Vowel Characters = 7
Number of Consonant Characters = 5