JavaScript Array Methods
Interactive reference for all JS array methods with live editable code examples. Edit, run, and learn.
15.9Kuses
8.1/10(106)
Adding & Removing
Methods that add or remove elements
push()Adds elements to the endMutatesReturns: New length
arr.push(...items)pop()Removes the last elementMutatesReturns: Removed element
arr.pop()unshift()Adds elements to the beginningMutatesReturns: New length
arr.unshift(...items)shift()Removes the first elementMutatesReturns: Removed element
arr.shift()splice()Adds/removes elements at any positionMutatesReturns: Array of removed
arr.splice(start, deleteCount, ...items)Transformation
Methods that create new transformed arrays
map()Creates a new array by transforming each elementNon-mutatingReturns: New array
arr.map(callback(item, index, arr))filter()Creates a new array with elements that pass a testNon-mutatingReturns: New array
arr.filter(callback(item, index, arr))reduce()Reduces array to single value by accumulatingNon-mutatingReturns: Accumulated value
arr.reduce(callback(acc, item, index, arr), initialValue)flat()Flattens nested arrays to specified depthNon-mutatingReturns: New array
arr.flat(depth)flatMap()Maps then flattens one level deepNon-mutatingReturns: New array
arr.flatMap(callback)slice()Returns a shallow copy of a portionNon-mutatingReturns: New array
arr.slice(start, end)concat()Merges arrays togetherNon-mutatingReturns: New array
arr.concat(...arrays)Search & Test
Methods for finding elements and testing conditions
find()Returns first element that passes a testNon-mutatingReturns: Element or undefined
arr.find(callback(item, index, arr))findIndex()Returns index of first matching elementNon-mutatingReturns: Index or -1
arr.findIndex(callback)indexOf()Returns first index of an elementNon-mutatingReturns: Index or -1
arr.indexOf(item, fromIndex)includes()Checks if array contains an elementNon-mutatingReturns: Boolean
arr.includes(item, fromIndex)every()Tests if ALL elements passNon-mutatingReturns: Boolean
arr.every(callback)some()Tests if ANY element passesNon-mutatingReturns: Boolean
arr.some(callback)Sorting & Ordering
Methods that change element order
sort()Sorts elements in placeMutatesReturns: Sorted array
arr.sort(compareFn)reverse()Reverses order of elements in placeMutatesReturns: Reversed array
arr.reverse()toSorted()Returns a new sorted array (non-mutating)Non-mutatingReturns: New sorted array
arr.toSorted(compareFn)toReversed()Returns a new reversed array (non-mutating)Non-mutatingReturns: New reversed array
arr.toReversed()Iteration
Methods for looping over elements
forEach()Calls a function for each element (no return value)Non-mutatingReturns: undefined
arr.forEach(callback(item, index, arr))entries()Returns iterator of [index, value] pairsNon-mutatingReturns: Iterator
arr.entries()keys()Returns iterator of indicesNon-mutatingReturns: Iterator
arr.keys()values()Returns iterator of valuesNon-mutatingReturns: Iterator
arr.values()Conversion
Methods that convert arrays to other types
join()Joins elements into a stringNon-mutatingReturns: String
arr.join(separator)toString()Converts array to comma-separated stringNon-mutatingReturns: String
arr.toString()Array.from()Creates array from iterable or array-likeNon-mutatingReturns: New array
Array.from(iterable, mapFn)Array.isArray()Checks if value is an arrayNon-mutatingReturns: Boolean
Array.isArray(value)Other
Additional useful methods
fill()Fills elements with a static valueMutatesReturns: Modified array
arr.fill(value, start, end)copyWithin()Copies part of array to another location in same arrayMutatesReturns: Modified array
arr.copyWithin(target, start, end)with()Returns new array with element replaced at indexNon-mutatingReturns: New array
arr.with(index, value)at()Returns element at index (supports negative)Non-mutatingReturns: Element
arr.at(index)⚡ Pro OptionsSponsored
Some links on this page are affiliate links. If you click and make a purchase, we may earn a commission at no extra cost to you.
Recommended Products
Ad⌨️Mechanical KeyboardsShop →🖥️Ultrawide MonitorsShop →🪑Standing DesksShop →🎧Noise Cancelling HeadphonesShop →📚Programming BooksShop →💻Laptop StandsShop →🖱️Wireless MouseShop →🔌USB-C HubShop →👓Blue Light GlassesShop →🖥️Desk PadShop →
Affiliate Disclosure: As an Amazon Associate, ToolBird earns from qualifying purchases. Links above are affiliate links — if you buy through them, we may earn a small commission at no extra cost to you.
Disclaimer: This tool is provided as-is for informational and educational purposes only.