C# | String.ToLowerInvariant Method Last Updated : 11 Jul, 2025 Summarize Comments Improve Suggest changes Share Like Article Like Report String.ToLowerInvariant Method is used to get a copy of this String object converted to lowercase using the casing rules of the invariant culture. Here, "invariant culture" represents a culture that is culture-insensitive. Syntax: public string ToLowerInvariant (); Return value: The return type of this method is System.String. This method returns a string which is a lowercase equivalent of the current string. Below given are some examples to understand the implementation in a better way: Example 1: C# // C# program to illustrate // ToLowerInvariant() method using System; class GFG { // Main method static public void Main() { // variables string strA = "WelCome tO GeeKSfOrGeeKs"; string strB; // Convert strA into lowercase // using ToLowerInvariant() method strB = strA.ToLowerInvariant(); // Display string before ToLowerInvariant() method Console.WriteLine("String before ToLowerInvariant:"); Console.WriteLine(strA); Console.WriteLine(); // Display string after ToLowerInvariant() method Console.WriteLine("String after ToLowerInvariant:"); Console.WriteLine(strB); } } Output: String before ToLowerInvariant: WelCome tO GeeKSfOrGeeKs String after ToLowerInvariant: welcome to geeksforgeeks Example 2: C# // C# program to illustrate // ToLowerInvariant() Method using System; public class GFG { // Main method static public void Main() { // calling function Convert("GEeks"); Convert("geeks"); Convert("GEEKS"); } static void Convert(String value) { // Display strings Console.WriteLine("String 1: {0}", value); // Convert string into Lowercase // using ToLowerInvariant() method value = value.ToLowerInvariant(); // Display the Lowercase strings Console.WriteLine("String 2: {0}", value); } } Output: String 1: GEeks String 2: geeks String 1: geeks String 2: geeks String 1: GEEKS String 2: geeks Note: The invariant culture represents a culture that is culture-insensitive. It is associated with the English language but not with a specific country or region.ToLowerInvariant() method does not modify the value of the current instance. Instead, it returns a new string in which all characters in the current instance are converted to lowercase.This method can't be overloaded if you try to overload this method, it will give you compile-time error. Reference: https://learn.microsoft.com/en-us/dotnet/api/system.string.tolowerinvariant?view=netframework-4.7.2 Comment More infoAdvertise with us Next Article C# String ToLower() Method A ankita_saini Follow Improve Article Tags : C# CSharp-method CSharp-string Similar Reads C# | String.ToUpperInvariant Method String.ToUpperInvariant Method is used to get a copy of this String object converted to uppercase using the casing rules of the invariant culture. Here "invariant culture" represents a culture that is culture-insensitive.Syntax: public string ToUpperInvariant (); Return Value: The return type of thi 2 min read C# String ToLower() Method In C#, the ToLower() method is a string method used to convert all uppercase characters in a string to lowercase. If a character does not have a lowercase equivalent, such as a special symbol, it remains unchanged. This method is particularly useful when performing case-insensitive string comparison 3 min read C# | Char.ToLowerInvariant(Char) Method This method is used to converts the value of a Unicode character to its lowercase equivalent using the casing rules of the invariant culture. Syntax: public static char ToLowerInvariant (char c); Here, c is the Unicode character to convert. Return Value: This method returns the lowercase equivalent 2 min read C# String ToUpper() Method In C#, the ToUpper() method is used to convert all characters in a string to uppercase. If a character has an uppercase letter, it is converted, otherwise, it remains unchanged. Special characters and symbols are unaffected. This method is commonly used for case-insensitive comparisons and text form 2 min read C# | Uri.ToString() Method Uri.ToString( ) Method is used to get a canonical string representation for the specified Uri instance. Syntax: public override string ToString (); Return Value: This method returns a String instance that contains the unescaped canonical representation of the Uri instance. All characters are unescap 2 min read C# | Char.ToUpperInvariant(Char) Method This method is used to converts the value of a Unicode character to its uppercase equivalent using the casing rules of the invariant culture. Syntax: public static char ToUpperInvariant (char c); Here, c is the Unicode character to convert. Return Value: This method returns the uppercase equivalent 2 min read Like