JavaScript Array concat() Method Last Updated : 15 Jul, 2024 Comments Improve Suggest changes Like Article Like Report The concat() method concatenates (joins) two or more arrays. It returns a new array, containing the joined arrays. This method is useful for combining arrays without modifying the originals.Syntax:let newArray1 = oldArray.concat()let newArray2 = oldArray.concat(value0)let newArray3 = oldArray.concat(value0,value1)..............let newArray = oldArray.concat(value1 , [ value2, [ ...,[ valueN]]])Parameters:The parameters of this method are the arrays or the values that need to be added to the given array. The number of arguments to this method depends upon the number of arrays or values to be merged.Return value: This method returns a newly created array that is created after merging all the arrays passed to the method as arguments. Example 1: Below is an example of the Array concat() method to join three arrays. JavaScript // JavaScript code for concat() method function func() { let num1 = [11, 12, 13], num2 = [14, 15, 16], num3 = [17, 18, 19]; console.log(num1.concat(num2, num3)); } func(); Output[ 11, 12, 13, 14, 15, 16, 17, 18, 19 ]Example 2: In this example, the method concat() concatenates all the arguments passed to the method with the given array into one array which it returns as the answer. JavaScript // JavaScript code for concat() method function func() { let alpha = ["a", "b", "c"]; console.log(alpha.concat(1, [2, 3])); } func(); Output[ 'a', 'b', 'c', 1, 2, 3 ]Example 3: In this example, the method concat() concatenates both arrays into one array which it returns as the answer. JavaScript // JavaScript code for concat() method function func() { let num1 = [[23]]; let num2 = [89, [67]]; console.log(num1.concat(num2)); } func(); Output[ [ 23 ], 89, [ 67 ] ]We have a complete list of Javascript Array methods, to check those please go through this Javascript Array Complete reference article.Supported Browsers: The browsers supported by the JavaScript Array concat() method are listed below:Chrome 51 Edge 15 Firefox 54 Safari 10 Opera 38 Comment More infoAdvertise with us Next Article JavaScript Array copyWithin() Method H HGaur Follow Improve Article Tags : Misc JavaScript Web Technologies javascript-array JavaScript-Methods +1 More Practice Tags : Misc Similar Reads JavaScript Array() Constructor The Array() constructor is used to create Array objects and the array constructor can be called with or without a new keyword, both can create a new Array.Syntax:new Array(Value1, Value2, ...);new Array(ArrayLength);Array(Value1, Value2, ...);Array(ArrayLength);Parameters: ValueN: An array initializ 2 min read JavaScript Array constructor Property The JavaScript Array constructor property is used to return the constructor function for an array object. 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